This number is a prime.

+ The largest 4-digit prime with 4 distinct digits. Curiously, it is also an emirp whose sum of digits is the square of a prime. [Post]

+ The first case of two consecutive balanced primes that are both distinct-digit primes and emirps. [Loungrides]

+ The largest 4-digit distinct-digit emirp abcd such that abbcccdddd is also emirp, i.e., 9887771111. [Loungrides]

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