N = int(input())
def factorization(n):
    arr = []
    temp = n
    for i in range(2, int(-(-n**0.5//1))+1):
        if temp%i==0:
            cnt=0
            while temp%i==0:
                cnt+=1
                temp //= i
            arr.append([i, cnt])

    if temp!=1:
        arr.append([temp, 1])

    if arr==[]:
        arr.append([n, 1])

    return arr

p = factorization(N)
#print(p)
ans = 1
for lst in p:
    ans *= int((lst[0]**(lst[1]+1)-1)/(lst[0]-1))
print(ans)