What is a PRP ?
A PRP is a probable prime number, a number that nobody knows how to prove
or disprove its primality.
Here are some criterions that can be used to recognize these numbers
:
- N does not have any prime factor up to 2^32.
- N cannot be trivially written into a product.
- Take 3 square-free consecutive bases such that (b1/N)=(b2/N)=(b3/N)= -1. N
should be such that b1^((N-1)/2)=b2^((N-1)/2)=b3^((N-1)/2)= -1 (mod N).
- Take a prime base such that (b/N)= -1 and b<>b1<>b2<>b3.
N should pass the strong test in base b.
- or more (if someone has got an idea) !!!
Submit your PRPs
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See the Latest PRPs
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| Rank |
Probable prime |
Digits (> 50000) |
Who ? |
When ? |
| 6501 | (529*10^118554-7)/9 | 118556 | Robert Price | 08/2021 |
| 6502 | 26712^26777-26777^26712 | 118534 | Norbert Schneider | 07/2021 |
| 6503 | (2^393661+2666)/2 | 118504 | Stefano Morozzi | 09/2020 |
| 6504 | (2^393650+1614)/2 | 118501 | Stefano Morozzi | 09/2020 |
| 6505 | 27655^19264+19264^27655 | 118495 | Hans Havermann | 02/2021 |
| 6506 | 10^118485+469413 | 118486 | Patrick De Geest | 05/2021 |
| 6507 | 10^118485-50001 | 118485 | Robert Price | 08/2020 |
| 6508 | (2^393528+1030)/2 | 118464 | Stefano Morozzi | 09/2020 |
| 6509 | 2^393427+75683 | 118434 | Enzo Doria | 04/2016 |
| 6510 | 2^393376-114749 | 118418 | Enzo Doria | 04/2015 |
| 6511 | (65*10^118417+493)/9 | 118418 | Robert Price | 08/2021 |
| 6512 | 30960^6671+6671^30960 | 118397 | Hans Havermann | 02/2021 |
| 6513 | (2^393234+2010)/2 | 118375 | Stefano Morozzi | 09/2020 |
| 6514 | (2^393205+3030)/2 | 118367 | Stefano Morozzi | 09/2020 |
| 6515 | (2^393191+2174)/2 | 118362 | Stefano Morozzi | 09/2020 |
| 6516 | 2^393180+73 | 118359 | Lelio R Paula | 04/2013 |
| 6517 | 3*2^393125+5 | 118343 | Jon Grantham | 07/2023 |
| 6518 | 27546^19771+19771^27546 | 118339 | Hans Havermann | 02/2021 |
| 6519 | 822^40595-40595^822 | 118330 | Norman Luhn | 09/2024 |
| 6520 | p(23881)#/2+256 | 118328 | Robert Price | 05/2017 |
| 6521 | (10^118324+359)/9 | 118324 | Serge Batalov | 12/2014 |
| 6522 | (2^393048+570)/2 | 118319 | Stefano Morozzi | 09/2020 |
| 6523 | p(23879)#/2+64 | 118317 | Robert Price | 03/2017 |
| 6524 | 2^393033+20147 | 118315 | Enzo Doria | 08/2023 |
| 6525 | 8*10^118308+59 | 118309 | Robert Price | 11/2021 |
| 6526 | Phi(186197,5) | 118308 | Henri Lifchitz | 12/2025 |
| 6527 | 9*10^118282+29 | 118283 | Robert Price | 03/2022 |
| 6528 | (9*35^76602+12877)/34 | 118279 | Eric Chen | 05/2025 |
| 6529 | (238*10^118265-1)/3 | 118267 | Robert Price | 04/2020 |
| 6531 | (53*10^118216+1)/9 | 118217 | Serge Batalov | 11/2010 |
| 6530 | (2^392707+1710)/2 | 118217 | Stefano Morozzi | 09/2020 |
| 6532 | (7*2^392697+1)/15 | 118214 | Renaud Lifchitz | 03/2011 |
| 6533 | Phi(89679,-100) | 118192 | Henri Lifchitz | 12/2025 |
| 6534 | (157^53819-1)/156 | 118179 | Alexander Zhirkov | 06/2016 |
| 6535 | (2^392567+2750)/2 | 118175 | Stefano Morozzi | 01/2021 |
| 6536 | 55*10^118172+3 | 118174 | Robert Price | 07/2022 |
| 6537 | (19*2^392551+1)/3 | 118171 | Lelio R Paula | 04/2014 |
| 6538 | 27185^22222+22222^27185 | 118168 | Hans Havermann | 01/2021 |
| 6539 | 2^392516-29219 | 118160 | Enzo Doria | 07/2015 |
| 6540 | 66*10^118155+7 | 118157 | Robert Price | 07/2020 |
| 6541 | Phi(177231,10) | 118152 | Maksym Voznyy | 09/2015 |
| 6542 | 2^392413-112123 | 118129 | Enzo Doria | 06/2014 |
| 6543 | 27491^19798+19798^27491 | 118119 | Hans Havermann | 02/2021 |
| 6544 | (49*10^118109-319)/9 | 118110 | Robert Price | 10/2021 |
| 6545 | (2^392342+5)/27 | 118106 | Lelio R Paula | 04/2014 |
| 6546 | (2^392333+1782)/2 | 118104 | Stefano Morozzi | 01/2021 |
| 6547 | 2^392300-1841429 | 118095 | Enzo Doria | 06/2015 |
| 6548 | 3*2^392260-5 | 118083 | Jon Grantham | 07/2023 |
| 6549 | 2^392220+75241 | 118070 | Enzo Doria | 04/2016 |
| 6550 | 27836^17409+17409^27836 | 118047 | Hans Havermann | 02/2021 |
| 6551 | (13^118026)%(10^118026) | 118026 | Henri Lifchitz | 05/2025 |
| 6552 | 10^118009+664447 | 118010 | Patrick De Geest | 07/2018 |
| 6553 | 10^118009-20001 | 118009 | Robert Price | 01/2018 |
| 6554 | (14*10^117991+61)/3 | 117992 | Robert Price | 12/2018 |
| 6555 | 2^391933+5897 | 117984 | Yves Minet | 02/2011 |
| 6556 | 2^391912-1849259 | 117978 | Enzo Doria | 08/2015 |
| 6557 | (2*34^77029+1043)/11 | 117968 | Eric Chen | 08/2023 |
| 6558 | 5*2^391836-3 | 117956 | Jon Grantham | 07/2023 |
| 6559 | 28357^14440+14440^28357 | 117953 | Hans Havermann | 02/2021 |
| 6560 | (2^391812+5)/14181 | 117944 | Lelio R Paula | 04/2014 |
| 6561 | 85^61124-61124^85 | 117934 | Norman Luhn | 09/2024 |
| 6562 | (7*10^117930-79)/9 | 117930 | Robert Price | 01/2021 |
| 6563 | 27531^19168+19168^27531 | 117904 | Hans Havermann | 02/2021 |
| 6564 | (46*10^117902+683)/9 | 117903 | Robert Price | 03/2019 |
| 6565 | 26349^26668-26668^26349 | 117893 | Frank Doornink | 03/2024 |
| 6566 | 27670^18189+18189^27670 | 117869 | Hans Havermann | 02/2021 |
| 6567 | (7*2^391521+1)/285 | 117858 | Lelio R Paula | 04/2014 |
| 6568 | (56*10^117856+583)/9 | 117857 | Robert Price | 08/2021 |
| 6569 | 32169^4606+4606^32169 | 117846 | Hans Havermann | 02/2021 |
| 6570 | (71*10^117803-143)/9 | 117804 | Robert Price | 10/2021 |
| 6571 | 2^391324+90901 | 117801 | Yves Minet | 02/2011 |
| 6572 | 2^391301-1859923 | 117794 | Enzo Doria | 03/2016 |
| 6573 | 2^391261-4131 | 117782 | Yves Minet | 02/2018 |
| 6574 | (2^391211+554)/2 | 117766 | Stefano Morozzi | 09/2020 |
| 6575 | 816^40445-40445^816 | 117764 | Norman Luhn | 09/2024 |
| 6576 | 38434^1157+1157^38434 | 117737 | Hans Havermann | 01/2021 |
| 6577 | (2^391115-7)/11791 | 117734 | Lelio R Paula | 04/2014 |
| 6578 | (85*10^117719+473)/9 | 117720 | Robert Price | 01/2020 |
| 6579 | (2^391049+582)/2 | 117718 | Stefano Morozzi | 09/2020 |
| 6580 | (21*23^86445-197)/22 | 117715 | Eric Chen | 08/2023 |
| 6581 | 31083^6122+6122^31083 | 117709 | Hans Havermann | 02/2021 |
| 6582 | 2^390960+1880881 | 117691 | Enzo Doria | 11/2016 |
| 6583 | (71*10^117685+91)/9 | 117686 | Robert Price | 04/2022 |
| 6585 | 2^390897-1860553 | 117672 | Enzo Doria | 11/2015 |
| 6584 | (61*10^117671+47)/9 | 117672 | Robert Price | 07/2022 |
| 6586 | 2^390889-115003 | 117670 | Enzo Doria | 06/2015 |
| 6587 | 12^109010+35 | 117642 | Riley Fisher | 08/2023 |
| 6588 | 2^390779-30337 | 117637 | Paul Bourdelais | 02/2012 |
| 6589 | (2^390735+378)/2 | 117623 | Stefano Morozzi | 02/2021 |
| 6590 | 11^112916-780 | 117590 | Enzo Doria | 12/2012 |
| 6591 | 27641^17916+17916^27641 | 117564 | Hans Havermann | 02/2021 |
| 6592 | 27906^16321+16321^27906 | 117561 | Hans Havermann | 02/2021 |
| 6593 | 27294^20275+20275^27294 | 117555 | Hans Havermann | 02/2021 |
| 6594 | (2^390473+1002)/2 | 117544 | Stefano Morozzi | 09/2020 |
| 6595 | 35912^1875+1875^35912 | 117541 | Hans Havermann | 02/2021 |
| 6596 | (16^97613-5^97613)/11 | 117537 | Robert Price | 07/2013 |
| 6597 | (2^390438+1774)/2 | 117534 | Stefano Morozzi | 01/2021 |
| 6598 | (2^390418+1722)/2 | 117528 | Stefano Morozzi | 09/2020 |
| 6599 | (2^390403+654)/2 | 117523 | Stefano Morozzi | 09/2020 |
| 6600 | (2^390343+2246)/2 | 117505 | Stefano Morozzi | 01/2021 |
| 6601 | 28043^15478+15478^28043 | 117493 | Hans Havermann | 02/2021 |
| 6602 | Phi(247237,3) | 117487 | Henri Lifchitz | 12/2025 |
| 6603 | (17*2^390272+1)/1983 | 117482 | Lelio R Paula | 04/2014 |
| 6604 | 37077^1474+1474^37077 | 117479 | Hans Havermann | 01/2021 |
| 6605 | 31^78759-30 | 117459 | Theodore Burton | 02/2007 |
| 6606 | (2^390176+1222)/2 | 117455 | Stefano Morozzi | 09/2020 |
| 6607 | (2^390133+1242)/2 | 117442 | Stefano Morozzi | 09/2020 |
| 6608 | (2^390013+2634)/2 | 117406 | Stefano Morozzi | 09/2020 |
| 6609 | 3*10^117402+61 | 117403 | Robert Price | 09/2020 |
| 6610 | 2^389998+37 | 117402 | Lelio R Paula | 03/2013 |
| 6611 | (2^389977+314)/2 | 117395 | Stefano Morozzi | 09/2020 |
| 6612 | (2^389921+342)/2 | 117378 | Stefano Morozzi | 01/2021 |
| 6613 | 71830^43+43^71830 | 117333 | Hans Havermann | 01/2021 |
| 6614 | (2^389768+1582)/2 | 117332 | Stefano Morozzi | 09/2020 |
| 6615 | 33802^2951+2951^33802 | 117292 | Hans Havermann | 02/2021 |
| 6616 | (2^561185)%L(561185) | 117281 | Henri Lifchitz | 05/2025 |
| 6617 | 26789^23866+23866^26789 | 117277 | Hans Havermann | 02/2021 |
| 6618 | 29^80192-1*80192^29 | 117273 | Dylan Delgado | 12/2019 |
| 6619 | (101*10^117260+7)/9 | 117262 | Robert Price | 02/2022 |
| 6620 | (13*10^117249+161)/3 | 117250 | Robert Price | 11/2018 |
| 6621 | 2^389478+43 | 117245 | Lelio R Paula | 03/2013 |
| 6622 | (298*10^117229-7)/3 | 117231 | Robert Price | 06/2020 |
| 6623 | (2^389416+342)/2 | 117226 | Stefano Morozzi | 01/2021 |
| 6624 | (29*2^389351-1)/9 | 117207 | Lelio R Paula | 04/2014 |
| 6625 | 5*10^117205+23 | 117206 | Robert Price | 03/2019 |
| 6626 | (2^389341-7)/3865 | 117200 | Lelio R Paula | 03/2014 |
| 6627 | 27272^19827+19827^27272 | 117195 | Hans Havermann | 01/2021 |
| 6628 | (2^389276+2650)/2 | 117184 | Stefano Morozzi | 09/2020 |
| 6629 | (844*10^117175-7)/9 | 117177 | Robert Price | 05/2021 |
| 6630 | 10^117142+209223 | 117143 | Patrick De Geest | 04/2018 |
| 6632 | 10^117142-1000000001 | 117142 | Robert Price | 03/2018 |
| 6631 | 10^117142-966057 | 117142 | Patrick De Geest | 04/2018 |
| 6633 | 10^117135+360577 | 117136 | Patrick De Geest | 07/2018 |
| 6634 | 10^117135-401 | 117135 | Robert Price | 01/2018 |
| 6635 | 26415^26488-26488^26415 | 117126 | Norbert Schneider | 05/2021 |
| 6636 | 4*10^117123+79 | 117124 | Robert Price | 08/2018 |
| 6637 | 2^389033-12797413 | 117111 | Enzo Doria | 04/2016 |
| 6638 | (2^388987+2634)/2 | 117097 | Stefano Morozzi | 09/2020 |
| 6639 | 2^388960-109505 | 117089 | Enzo Doria | 04/2014 |
| 6640 | 7*10^117082-57 | 117083 | Robert Price | 06/2020 |
| 6641 | 791^40398-40398^791 | 117081 | Norman Luhn | 09/2024 |
| 6642 | (2^388928-5)/569 | 117077 | Lelio R Paula | 03/2014 |
| 6643 | 2^388888-1529 | 117067 | Yves Minet | 01/2013 |
| 6644 | 10^117059+28879 | 117060 | Patrick De Geest | 05/2016 |
| 6645 | (10^117059-71)/1 | 117059 | Serge Batalov | 12/2014 |
| 6646 | (2^388854+3630)/2 | 117057 | Stefano Morozzi | 09/2020 |
| 6647 | (2^388842+2098)/2 | 117053 | Stefano Morozzi | 09/2020 |
| 6648 | (2^388789+3150)/2 | 117037 | Stefano Morozzi | 09/2020 |
| 6649 | (2^388748+378)/2 | 117025 | Stefano Morozzi | 02/2021 |
| 6650 | (693^41189-1)/692 | 117005 | Michael Stocker | 05/2020 |
| 6651 | (26*10^116999-503)/9 | 117000 | Robert Price | 07/2018 |
| 6652 | 20^89917-21 | 116985 | Anonymous | 09/2024 |
| 6653 | (2^388609+1554)/2 | 116983 | Stefano Morozzi | 09/2020 |
| 6654 | 38496^1093+1093^38496 | 116975 | Hans Havermann | 02/2021 |
| 6655 | 3^245154-6256 | 116969 | Enzo Doria | 05/2014 |
| 6656 | 5*10^116966-43 | 116967 | Robert Price | 01/2019 |
| 6657 | (748^40699-1)/747 | 116963 | Tom Wu | 08/2025 |
| 6658 | 2^388536-113495 | 116961 | Enzo Doria | 08/2014 |
| 6659 | (2^388512+382)/2 | 116954 | Stefano Morozzi | 02/2021 |
| 6660 | (8*32^77701+271)/31 | 116952 | Eric Chen | 11/2023 |
| 6661 | 2^388469-43 | 116941 | Lelio R Paula | 03/2013 |
| 6662 | 27417^18416+18416^27417 | 116939 | Hans Havermann | 02/2021 |
| 6663 | (2^388438+1842)/2 | 116932 | Stefano Morozzi | 02/2021 |
| 6664 | (7*2^388372-1)/111 | 116911 | Lelio R Paula | 04/2014 |
| 6665 | (7*2^388335-1)/25 | 116900 | Lelio R Paula | 04/2014 |
| 6666 | 2^388180+93 | 116854 | Donovan Johnson | 07/2008 |
| 6667 | (2^388167+2510)/2 | 116850 | Stefano Morozzi | 09/2020 |
| 6668 | (85*10^116842+293)/9 | 116843 | Robert Price | 12/2019 |
| 6669 | 35296^2043+2043^35296 | 116840 | Hans Havermann | 02/2021 |
| 6670 | (2^388081+7)/1179 | 116821 | Lelio R Paula | 03/2014 |
| 6671 | 38633^1056+1056^38633 | 116814 | Hans Havermann | 02/2021 |
| 6672 | 2^387946-113261 | 116784 | Enzo Doria | 07/2014 |
| 6673 | 28*36^75009+305 | 116739 | Eric Chen | 12/2022 |
| 6674 | 28363^13056+13056^28363 | 116737 | Hans Havermann | 02/2021 |
| 6675 | 2^387745+75557 | 116723 | Enzo Doria | 04/2016 |
| 6676 | (29*10^116719+313)/9 | 116720 | Robert Price | 04/2021 |
| 6677 | 29622^8699+8699^29622 | 116695 | Hans Havermann | 02/2021 |
| 6678 | (206*10^116687-17)/9 | 116689 | Robert Price | 01/2020 |
| 6679 | (7*10^116684+179)/3 | 116685 | Robert Price | 09/2018 |
| 6680 | 2^387554+71455 | 116666 | Enzo Doria | 04/2016 |
| 6681 | (602*10^116647-71)/9 | 116649 | Robert Price | 12/2021 |
| 6682 | 3^244461-10 | 116638 | Tyler NeSmith | 09/2022 |
| 6683 | (2^387447+78557)/365 | 116631 | Lelio R Paula | 12/2014 |
| 6684 | (2*10^116620+43)/9 | 116620 | Serge Batalov | 11/2022 |
| 6685 | (19*10^116617+287)/9/12893 | 116614 | Alfred Reich | 11/2022 |
| 6686 | (145*10^116610-1)/9 | 116612 | Serge Batalov | 12/2014 |
| 6687 | (25*10^116601-331)/9 | 116602 | Robert Price | 08/2018 |
| 6688 | 25791^26428-26428^25791 | 116587 | Frank Doornink | 03/2024 |
| 6690 | (17*2^387284-1)/59 | 116584 | Lelio R Paula | 04/2014 |
| 6689 | (2^387284+3726)/2 | 116584 | Stefano Morozzi | 09/2020 |
| 6691 | 2^387211+111546435 | 116563 | Paul Bourdelais | 10/2021 |
| 6692 | 10^116557+987654321 | 116558 | Robert Price | 12/2019 |
| 6693 | 10^116557+9141 | 116558 | Patrick De Geest | 02/2020 |
| 6694 | 10^116557-609431 | 116557 | Patrick De Geest | 02/2020 |
| 6695 | 209^50234-50234^209 | 116551 | Norman Luhn | 09/2024 |
| 6696 | (28*10^116546+41)/3 | 116547 | Robert Price | 07/2021 |
| 6697 | (2^387123+1814)/2 | 116536 | Stefano Morozzi | 02/2021 |
| 6698 | (2^387076+2046)/2 | 116522 | Stefano Morozzi | 09/2020 |
| 6699 | (2^387073+2570)/2 | 116521 | Stefano Morozzi | 09/2020 |
| 6700 | (7*10^116514-1)/3 | 116515 | Robert Price | 08/2022 |
| 6701 | (26*32^77406-390071011)/31 | 116508 | Eric Chen | 11/2023 |
| 6702 | 28846^10931+10931^28846 | 116500 | Hans Havermann | 02/2021 |
| 6703 | 10^116496+3593037 | 116497 | Paul Bourdelais | 10/2021 |
| 6704 | 272^47851-47851^272 | 116497 | Norman Luhn | 09/2024 |
| 6705 | (31*2^386968+1)/7 | 116490 | Lelio R Paula | 03/2014 |
| 6706 | (944^39157+1)/945 | 116489 | Jinyuan Wang | 12/2024 |
| 6707 | 2^386947+1869143 | 116483 | Enzo Doria | 05/2016 |
| 6709 | (30^78857-1)/29 | 116480 | Robert Price | 12/2011 |
| 6708 | Phi(78857,5#) | 116480 | Henri Lifchitz | 12/2025 |
| 6710 | (2^386903-3)/5 | 116469 | Lelio R Paula | 03/2014 |
| 6711 | 28107^13892+13892^28107 | 116441 | Hans Havermann | 02/2021 |
| 6712 | 29110^9957+9957^29110 | 116386 | Hans Havermann | 02/2021 |
| 6713 | 26469^24838+24838^26469 | 116335 | Hans Havermann | 01/2021 |
| 6714 | 2^386389-1864783 | 116315 | Enzo Doria | 03/2016 |
| 6715 | (8*32^77250-163)/31 | 116273 | Eric Chen | 11/2023 |
| 6716 | (31*2^386231-1)/1711 | 116266 | Lelio R Paula | 03/2014 |
| 6717 | 297^47012+47012^297 | 116250 | Norbert Schneider | 07/2018 |
| 6718 | (35*10^116223-341)/9 | 116224 | Robert Price | 08/2021 |
| 6719 | (2^386087-5)/40959 | 116220 | Lelio R Paula | 03/2014 |
| 6720 | (2^386054+714)/2 | 116214 | Stefano Morozzi | 09/2020 |
| 6721 | (10^116201+7)/39623 | 116197 | Alfred Reich | 06/2021 |
| 6722 | 2^385969-823 | 116189 | Yves Minet | 05/2012 |
| 6723 | 57^66162+2 | 116173 | Lelio R Paula | 08/2013 |
| 6724 | 2^385854+75049 | 116154 | Enzo Doria | 04/2016 |
| 6725 | (2^385832+2590)/2 | 116147 | Stefano Morozzi | 09/2020 |
| 6726 | 2^385775-109587 | 116130 | Enzo Doria | 04/2014 |
| 6727 | (14*10^116112-101)/3 | 116113 | Robert Price | 02/2019 |
| 6728 | Phi(236354,10)/24817171 | 116109 | Makoto Kamada | 08/2019 |
| 6729 | 3*10^116107+23 | 116108 | Robert Price | 03/2022 |
| 6730 | 28729^10990+10990^28729 | 116094 | Hans Havermann | 02/2021 |
| 6731 | 2^385622+71839 | 116084 | Enzo Doria | 04/2016 |
| 6733 | 2^385564+781 | 116067 | Lelio R Paula | 01/2012 |
| 6732 | (2^385565+1562)/2 | 116067 | Stefano Morozzi | 09/2020 |
| 6734 | (2^385563+378)/2 | 116066 | Stefano Morozzi | 02/2021 |
| 6735 | (2^385557+2214)/2 | 116064 | Stefano Morozzi | 09/2020 |
| 6736 | 29431^8776+8776^29431 | 116056 | Hans Havermann | 01/2021 |
| 6737 | (266*10^116024-17)/3 | 116026 | Robert Price | 07/2020 |
| 6738 | 30263^6820+6820^30263 | 116022 | Hans Havermann | 02/2021 |
| 6739 | 2^385410+71893 | 116020 | Enzo Doria | 04/2016 |
| 6740 | 38225^1084+1084^38225 | 116014 | Hans Havermann | 02/2021 |
| 6741 | 26548^23433+23433^26548 | 116011 | Hans Havermann | 02/2021 |
| 6742 | Phi(183801,-9) | 115960 | Henri Lifchitz | 12/2025 |
| 6743 | 12^107422-11 | 115928 | Riley Fisher | 12/2023 |
| 6744 | (25*2^385091+1)/27 | 115924 | Lelio R Paula | 04/2014 |
| 6745 | (11*10^115910-131)/3 | 115911 | Robert Price | 09/2018 |
| 6746 | 2^384953-111943 | 115883 | Paul Bourdelais | 02/2012 |
| 6747 | 43^70942-2 | 115882 | Lelio R Paula | 04/2014 |
| 6748 | (94*10^115879-7)/3 | 115881 | Robert Price | 03/2020 |
| 6749 | 7*10^115863+3 | 115864 | Robert Price | 08/2015 |
| 6750 | 2^384834+93 | 115847 | Donovan Johnson | 07/2008 |