28503...58273 (991-digits)

This number is a prime.

+ 7^1172 - 1172^11; a prime of form 7^n - n^11, similar to Pomerance's Convenience Store numbers (see entry for PC 1999). It was certified prime with Primo. Also, if we sum the factorials of the digits of 7^1172 - 1172^11 we get 38125657, a prime. [Earls]

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