18060109

This number is a prime.

+ The smallest invertible prime p containing all of the invertible digits {0, 1, 6, 8, 9} such that (p^n + k) is an emirp, where k is an integer formed by concatenating in ascending order the first n digits, n times each of them, (case n=6), i.e., 1061689^6 + 111111222222333333444444555555666666. [Bajpai]

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