#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
typedef long long ll;
int main(){
  ll N=0;cin>>N;
  ll a=N;
  if(N%2==0) a=0;
  if(N>1) a+=1;
  if(a>1){
    vector<ll> v;
    for(ll i=3;i*i<=N;i+=2){
      if(N%i==0){
        v.push_back(i);
        v.push_back(N/i);
      }
    }
    sort(v.begin(),v.end());
    auto result=unique(v.begin(),v.end());
    v.erase(result,v.end());
    for(ll i=0;i<v.size();++i){
      a+=v[i];
    }
  }
  cout<<a<<endl;
}