N = int(raw_input())

if N <= 2:
    print 1
    exit()
elif N == 3:
    print 4
    exit()

n = N
i = 2
ans = 1
while i*i <= n:
    p = 0
    while n % i == 0:
        n /= i
        p += 1
    if p > 0:
        ans *= (pow(i, p + 1) - 1) / (i - 1)
    i += 1
if n > 1:
    ans *= 1 + n

print ans