#!/usr/bin/env python3
import fractions


def solve(n: int) -> int:
    a = 0
    b = 0
    for d in range(1, n + 1):
        if n % d == 0:
            a += d
            b += fractions.Fraction(1, d)
    return a // b


# generated by oj-template v4.8.0 (https://github.com/online-judge-tools/template-generator)
def main():
    N = int(input())
    a = solve(N)
    print(a)


if __name__ == '__main__':
    main()