# 472393

This number is a prime.

If a number can be written both as 2*a*^{2} + 1 and as 3*b*^{3} + 1, it must be of the form 648*k*^{6} + 1. The smallest prime of this form is not only 472393, where *k* = 3, but curiously *k* = 4 and *k* = 5 also. [Hartley]

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