11939
This number is a prime.
The only cyclic emirp with five digits.
11939 and 13159 are the first case of two emirps of forms p*q*r-s*t*u and p*q*r+s*t*u where p, q, r, s, t, u are primes formed from the distinct digits, 1 through 9, i.e., 11939=3*47*89-2*5*61, 13159=3*47*89+2*5*61. [Loungrides]
Printed from the PrimePages <t5k.org> © G. L. Honaker and Chris K. Caldwell