123457

This number is a prime.

+ When you remove the penultimate (next to the last) digit of 123457 you will end up with yet another prime. Repeat the process for four more primes. [Brod]

+ The smallest prime formed from the first six imperfect numbers in order. [Beedassy]

+ The sum of the repunit number 111111 and all truncations of itself plus one is prime. [Loungrides]

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