Found with PFGW Version 3.7.5

6921^8800-8800^6921 is 2-PRP! (22.4282s+0.0017s)
6921^8800-8800^6921 is 3-PRP! (22.1336s+0.0013s)
6921^8800-8800^6921 is 5-PRP! (22.3717s+0.0014s)
6921^8800-8800^6921 is 7-PRP! (21.7895s+0.0016s)
6921^8800-8800^6921 is 11-PRP! (21.8136s+0.0015s)

Primality testing 6921^8800-8800^6921 [N-1/N+1, Brillhart-Lehmer-Selfridge]
Running N-1 test using base 3
Running N+1 test using discriminant 13, base 1+sqrt(13)
Calling N-1 BLS with factored part 0.06% and helper 0.01% (0.20% proof)
6921^8800-8800^6921 is Fermat and Lucas PRP! (109.4511s+0.0027s)

To be completed...