def is_truncatable(num): digits = elib.to_digits(num) for i in xrange(1, len(digits)): if not elib.is_prime(elib.from_digits(digits[i:])) or \ not elib.is_prime(elib.from_digits(digits[:i])): return False return True
import elib import itertools for i in range(9, 1, -1): for perm in itertools.permutations(range(i, 0, -1)): n = elib.from_digits(perm) if elib.is_prime(n): print(n) return