31111...11113 (127-digits)

This number is a prime.

              3111111 1111111111 1111111111 1111111111 1111111111 1111111111
1111111111 1111111111 1111111111 1111111111 1111111111 1111111111 1111111113

+ This the 5th number of this form. Note that it has a Mersenne prime number of digits and a palindromic prime digital sum. [Patterson]

Printed from the PrimePages <primes.utm.edu> © G. L. Honaker and Chris K. Caldwell