#! /usr/bin/python def is_prime(n): if (n == 2) or (n == 3): return True if (n < 2) or (n %2 == 0): return False if n < 9: return True if n % 3 == 0: return False sqrt_n = int(n ** 0.5) step = 5 while step <= sqrt_n: if n % step == 0: return False if n % (step + 2) == 0: return False step += 6 return True def is_circular_prime(n): num = str(n) for i in range(len(num)): if not is_prime(int(num[i:] + num[:i])): return False return True if __name__ == '__main__': num = int(input()) result = (sum(1 for n in range(2, num) if is_circular_prime(n))) print(result)