Found with PFGW Version 3.7.5

9973^10820-10820^9973 is 2-PRP! (37.9276s+0.0032s)
9973^10820-10820^9973 is 3-PRP! (37.8838s+0.0036s)
9973^10820-10820^9973 is 5-PRP! (37.3092s+0.0028s)
9973^10820-10820^9973 is 7-PRP! (37.5435s+0.0029s)
9973^10820-10820^9973 is 11-PRP! (37.4171s+0.0049s)

Primality testing 9973^10820-10820^9973 [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)
Calling N-1 BLS with factored part 0.02% and helper 0.02% (0.10% proof)
9973^10820-10820^9973 is Fermat and Lucas PRP! (188.6817s+0.0035s)

To be completed...