import sys
from decimal import Decimal, ROUND_HALF_UP

primes = [2, 3, 5, 7, 11, 13]
composites = {4, 6, 8, 9, 10, 12}

K = int(sys.stdin.readline())

if K == 0:
    print("0.00000000000000000")
else:
    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)
        prob_rounded = prob.quantize(Decimal('0.00000000000000000'), rounding=ROUND_HALF_UP)
        print(prob_rounded)