K = int(input())
P = [2, 3, 5, 7, 11, 15]
C = [4, 6, 8, 9, 10, 12]

cnt = 0
for i in range(36):
    d, m = divmod(i, 6)
    if P[d] * C[m] == K:
        cnt += 1
print(cnt / 36)