7283

This number is a prime.

+ Which primes are simultaneously of the form 10s-7 and 10c-7, where s is an integer square and c is a cube? The first one is 3 (s=c=1), and the next largest one is 7283 = 10(9^3)-7 = 10(27^2)-7. The next one after 7283 is 466553. [Keith]

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