def primeFactors(n):
    result = []
    factor = 0
    factorCount = 0
    q = n
    if n >= 2:
        i = 2
        while i*i<=n:
            if q % i == 0:
                if i != factor:
                    factor = i
                    factorCount = 1
                else:
                    factorCount+=1
                q //= i;
            else:
                if factor > 0:
                    result.append((factor, factorCount))
                    factor = 0
                i+=1
    if q > 1:
        result.append((q, 1))

    return result

n=int(input())
primes = primeFactors(n)
ans = 1
for (p, f) in primes:
    ans *= (pow(p, f+1)-1)//(p-1)
print(ans)