from decimal import Decimal

k = int(input())

if k == 0:
    print("0.00000000000000000")
else:
    primes = [2, 3, 5, 7, 11, 13]
    composites = {4, 6, 8, 9, 10, 12}
    count = 0
    
    for p in primes:
        if k % p != 0:
            continue
        c = k // p
        if c in composites:
            count += 1
    
    if count == 0:
        print("0.00000000000000000")
    else:
        prob = Decimal(count) / Decimal(36)
        print("{0:.17f}".format(prob))