n = int(input())
sb = []

for i in range(2,n+1):
    t = 0
    while n % i == 0:
        t += 1
        n //= i
    if t != 0:
        sb.append([i,t])

def souwa(x):
    r, n = x
    return (r**(n+1) - 1) / (r - 1)

s = 1
for i in sb:
    s *= souwa(i)

print(int(s))