99999999999999999991999

This number is a prime.

                                                   999 9999999999 9999991999

+ The smallest near-repdigit prime whose sum of digits is a near-repdigit prime substring (199). Note that the latter is the smallest near-repdigit prime whose sum of digits is a prime substring (19). [Beedassy]

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