static bool IsCircularPrime(Int64 value)
{
var numbers = value.Split();
// todo permutations with only 13, 31 for 13 (make it)
var permutations = numbers.GetPermutations(value.ToString().Length);
var rotations = new List<Int64>();
permutations.ToList().ForEach(p => rotations.Add(long.Parse(String.Concat(p))));
return rotations.All(v => ps.Primes.Contains(v));
}