#include<iostream>
#include<algorithm>
#include<vector>
#include<string>
#include<utility>
#include<map>
#include<set>
#include<queue>
#include<stack>
#include<functional>
#include<math.h>
#include<random>
#include <bitset>
using namespace std;
#define N (1000000000+7)
//#define N 998244353
#define INF 1e16
typedef long long ll;
typedef pair<int,int> P;
typedef pair<int,P> Q;

const int inf = (int)1e9; 

ll dp[1000010][2];

int main(void){
    ll n;
    cin>>n;
    ll ans = 0;
    for(ll i=1;i*i<=n;i++){
        if(n%i==0){
            ll t = n/i;
            if(i==t)ans+=i;
            else ans+=i+t;
        }
    }
    cout<<ans<<endl;
    return 0;
}