#include <iostream>
#include <time.h>

using namespace std;

int sum_div(int);

int main()
{
    int n;
    cin>>n;
    cout<<sum_div(n);
    return 0;
}
int sum_div(int n){
    int i,sum=0;
    clock_t ceas1;
    ceas1=clock();
    for(i=1;i<=n;i++) {
        if(n%i==0){
            sum=sum+i;
        }
    }
    cout<<clock()-ceas1<<endl;
    return sum;
}