/*
    Created by binhnguyen
*/
/* Tinh tong tat ca cac uoc so cua so nguyen duong n */
 
#include <iostream>
using namespace std;
 
int main(){
    int n;
    do{
        cin >> n;
        if(n <= 0){
            cout << "\nNhap lai n = ";
        }
    }while(n <= 0);
    int sum = 0;
    for(int i = 1;i <= n;i++){
        if(n % i == 0){
            sum += i;
        }
    }
    cout << "\nSum = " << sum << '\n';
}