7772777
This number is a prime.
The only near-repdigit seven-digit palindromic wing prime
such that the product of itself and all truncations of
itself minus one, i.e.,7772777*777277*77727*7772*777*77*7-1
= 1528503743076224921408830427 is prime. [Bajpai]
(There is one curio for this number that has not yet been approved by an editor.)
Printed from the PrimePages <t5k.org> © G. L. Honaker and Chris K. Caldwell