22227...44441 (221-digits)

This number is a probable-prime (likely to be a prime but we have not (re-)proven it on this site).

                                                                2 2227777777
7777777777 7777777777 7777777777 7777777777 7755555555 5555555555 5555555999
9999999999 9999999999 9999999999 9999999999 9999999999 9999999999 9999999999
9999999933 3333333666 6666666666 6666666666 6666666666 6664444444 4444444441

+ Starting with a "most distinct digits prime" you can obtain two automorphic primes using the rule "d digits of each digit d" twice in cascade: 207593641 -> 2277777775555599999999933366666644441 -> etc. [Rivera]

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