#include "bits/stdc++.h"
using namespace std;
#define FOR(i,j,k) for(int (i)=(j);(i)<(int)(k);++(i))
#define rep(i,j) FOR(i,0,j)
#define each(x,y) for(auto &(x):(y))
#define mp make_pair
#define all(x) (x).begin(),(x).end()
#define debug(x) cout<<#x<<": "<<(x)<<endl
#define smax(x,y) (x)=max((x),(y))
#define smin(x,y) (x)=min((x),(y))
#define MEM(x,y) memset((x),(y),sizeof (x))
#define sz(x) (int)(x).size()
typedef long long ll;
typedef pair<int, int> pii;
typedef vector<int> vi;
typedef vector<ll> vll;

ll N;

int main(){
    while(cin >> N){
        ll ans = 0;
        if(N % 2 == 0)N /= 2;
        for(ll i = 1; i*i <= N; ++i){
            if(N%i == 0){
                ans += i;
                ll j = N / i;
                if(i != j)ans += j;
            }
        }
        cout << ans << endl;
    }
}