3895126220983308449519

This number is a prime.

                                                    38 9512622098 3308449519

3895126220983308449519 = (17-1)^(17+1) - 17^17 is the largest known prime of the form (p-1)^(p+1) - p^p where p is prime. Its sum of digits is a palindromic prime. [Post]