#!/usr/bin/python
a = [2, 3, 5, 7, 11, 13]
b = [4, 6, 8, 9, 10, 12]
k = int(raw_input())
res = 0
for x in a:
    for y in b:
        if x * y == k:
            res += 1
print float(res) / 36