554535251
This number is a prime.
554535251 is the smallest prime number formed by concatenating an
integer n > 1 with the alternating sequence n, n−1, n,
n−2, ..., n, 1. The next two such primes occur at n = 13
and n = 29. [Ahmed]
Printed from the PrimePages <t5k.org> © G. L. Honaker and Reginald McLean