This number is a prime.
The smallest emirp formed using only all of the digits of the decimal expansion of 1/7. [Beedassy]
The smallest prime (emirp also), formed by using all the
digits which can be digital root of mutidigit primes. [Gupta]
Printed from the PrimePages <t5k.org> © G. L. Honaker and Chris K. Caldwell