#include <bits/stdc++.h>
#include<string>
#include<map>
#include<cmath>
#define ll long long
using namespace std;
ll b,l,r,MOD=1e9,j,c=0,k,A[1000000],i,n,mi=INT_MAX,res=0,D[1000000],d=0,e,f,g,h,t=0;
string s;
int main()
{
	//freopen("standard.inp","r",stdin)
	//freopen("standard.out","w",stdout)
	cin>>n;
	for(i=1;i<=sqrt(n);i++)
	if(n%i==0) 
	t+=i+n/i;
	cout<<t;
}