package com.company;

import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        Long value = scanner.nextLong();
        double root = Math.sqrt((double) value);
        Long sum = 0L;
        for(Long i = 1L; i <= root;i++)
        {
            if(value % i == 0)
            {
                sum += i + (value / i);
            }
        }

        System.out.println(sum.toString());
    }
}