The number 1615201561 has the same digits as the 6th row of Pascal's triangle.

PFGW Version 1.2.0 for Windows [FFT v23.8]

Primality testing 10^24056+1615201561 [N-1/N+1, Brillhart-Lehmer-Selfridge]
Running N-1 test using base 3
Running N+1 test using discriminant 7, base 1+sqrt(7)
10^24056+1615201561 is Fermat and Lucas PRP!

To be completed...