47731...64991 (15092-digits)

This number is a prime.

Just showing those entries submitted by 'Broadhurst': (Click here to show all)

Call this prime P. Then Q=16*P-15 and R=(P-1)*(16*P+1)/9266506659322630097+1 are also primes. As of September 2003, N=P*Q*R was the largest known Carmichael number with precisely 3 prime factors. In other words, N divides (a^N-a) for every positive integer a. [Broadhurst]