from decimal import Decimal, ROUND_HALF_UP, getcontext

getcontext().rounding = ROUND_HALF_UP

K = int(input())
if K == 0:
    print("0.000000000000000000")
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
    prob = Decimal(count) / Decimal(36)
    formatted = prob.quantize(Decimal('1.000000000000000000'), rounding=ROUND_HALF_UP)
    print(formatted)