This number is a prime.
Single Curio View: (Seek other curios for this number)73 is the only Sheldon prime, i.e., i) whose binary representation is palindromic (10010012) and ii) which belongs to an emirp pair (Pn, Pm) such that subscripts (m, n) = (21, 12) are also reversals of each other and n has a prime decomposition 21 = 3*7 that concatenates back to Pm (Carl Pomerance, Chris Spicer, February 2019). [Beedassy]
Submitted: 2019-04-18 12:18:11; Last Modified: 2019-04-18 13:04:41.
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