#include <algorithm>
#include <cstdio>
#include <cstdlib>
#include <cctype>
#include <cmath>
#include <iostream>
#include <queue>
#include <list>
#include <stack>
#include <map>
#include <numeric>
#include <set>
#include <sstream>
#include <string>
#include <vector>
using namespace std;
#define REP(i,a,n) for(int i=(a); i<(int)(n); i++)
#define rep(i,n) REP(i,0,n)
#define FOR(it,c) for(__typeof((c).begin()) it=(c).begin(); it!=(c).end(); ++it)
#define ALLOF(c) (c).begin(), (c).end()
typedef long long ll;

vector<ll> factorize(ll x){
  vector<ll> ret;
  ll d, q;
  while(x>=4 && x%2==0){ret.push_back(2); x/=2;}
  d = 3; q = x/d;
  while(q>=d){
    if(x%d==0){ ret.push_back(d); x=q; }else{ d+=2; }
    q=x/d;
  }
  ret.push_back(x);
  return ret;
}

map<ll,int> ret;

void dfs(ll now, const vector< pair<ll,int> >& v, int id){
  ret[now] = 1;
  if(id>=v.size()) return;

  dfs(now,v,id+1);
  ll p = now;
  rep(i,v[id].second){
    p *= v[id].first;
    dfs(p,v,id+1);
  }
}

int main(){
  ios::sync_with_stdio(false);
  ll N;
  cin >> N;
  vector<ll> a = factorize(N);
  vector<ll> b = factorize(N-1);
  map<ll,int> ma, mb, mab;
  rep(i,a.size()){
    ma[a[i]]++;
    mb[a[i]]++;
  }
  rep(i,b.size()){
    mb[b[i]]++;
  }
  mb[2]--;
  FOR(it,ma){
    if(mb.count(it->first)>0){
      mab[it->first] = min(it->second, mb[it->first]);
    }
  }

  vector< pair<ll,int> > v;
  FOR(it,mab){
    v.push_back(make_pair(it->first,it->second));
  }
  dfs(1LL,v,0);
  ll sum = 0;
  FOR(it,ret){
    sum += it->first;
  }
  cout << sum << endl;
  return 0;
}