81615141210198641

This number is a prime.

                                                          8161514 1210198641

+ A prime formed by concatenating all the non-primes from 1 to 18, 1-4-6-8-9-10-12-14-15-16-18, then reversing the whole string. [Rivera]

Printed from the PrimePages <t5k.org> © G. L. Honaker and Chris K. Caldwell