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AOJ Challenge Problems 1

Anagrammatic Primes

A number is "prime" if it has no divisors other than itself and 1. For example, 23 is prime but 35 is not prime because 35 = 7 x 5. If the digits of a number are rearranged, then usually its primeness changes — for example, 35 is not prime but 53 is. For this problem, you must find numbers which are prime no matter how you rearrange their digits. For example, all of the numbers 113, 131 and 311 are prime, so we say that 113 is an "anagrammatic prime" (also 131 and 311 are anagrammatic primes).

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