135479

This number is a prime.

+ The smallest prime p such that replacing each digit d in decimal expansion of p with d^2 yields alternately a new semiprime and a new prime when done recursively five times, i.e., 135479 -> 1925164981 (semiprime); 1925164981-> 1814251361681641 (prime); 1814251361681641-> 164116425193613664136161 (semiprime); 164116425193613664136161-> 136161136164251819361936361619361361 (prime); 136161136164251819361936361619361361-> 1936136119361361642516418193618193693613618193619361 (semiprime). [Bajpai]

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