Quote:
Originally Posted by bhelmes
I noticed that the factors of Mp1 have the following proporty:
r odd and r  p1 then the factors f of Mp1 with f > p are f=1 mod r

Not quite. M12771 has a factor of 2089, among others. 12771 is divisible by 11. 2089 is 10 (mod 11), not 1.