27577787
This number is a prime.
The smallest prime concatenated from all of the 2-digit composite numbers that end in 7, i.e., 27, 57, 77, 87. [Loungrides]
(There are 14 curios for this number that have not yet been approved by an editor.)
Printed from the PrimePages <t5k.org> © G. L. Honaker and Reginald McLean