#include <iostream>
#include <algorithm>
#include <cmath>
#include <vector>
#include <complex>
#include <queue>
#include <deque>
#include <set>
#include <map>
#include <unordered_set>
#include <unordered_map>
#include <iomanip>
#include <assert.h>
#include <array>
#include <cstdio>

using namespace std;

#define REP(i,a,b) for(int i=a;i<(int)b;i++)
#define rep(i,n) REP(i,0,n)

typedef long long ll;

int main() {

  ll N; cin >> N; 

  ll X = N % 2 ? N : N / 2;
  ll Y = X;
  ll res = 0;
  for(ll x = 2; x*x<=Y; x++) {
    if(Y % x == 0) {
      res += x;
    }
    while(X % x == 0) X /= x;
  }

  if(X > 1) {
    res += X;
  }

  cout << ++res << endl;

  return 0;
}