# 6163

This number is a prime.

The smallest non-palindromic old-beast prime. Note that 6163, 61603, 616003, and 6160003 are all prime.

(6163, 6361) is the largest pair of primes formed from the concatenation in ascending and descending orders of two successive double-digit odd numbers. Can you find the two previous cases? [Loungrides]

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