This number is a prime.
Seven 1's prior to the digit 7 is an emirp. [Trotter]
The only prime formed from a prime digit preceded by an
equal number of ones. [Silva]
The lesser of the largest known twin prime pair (11111117, 11111119), where both primes are near repunit primes. [Gupta]
Printed from the PrimePages <t5k.org> © G. L. Honaker and Chris K. Caldwell