#include <bits/stdc++.h>

using namespace std;

#define int long long

bool check (int n)
{
  int s = 0;
  for (int i = 1; i <= sqrt(n); ++i)
  {
    if (n % i == 0)
    {
      s += i + n / i;
    }
  }
  int k = sqrt(n);
  if (k * k == n) s -= k;
  return s - n == n;
}
int n, d = 0;
main() {
  freopen("shh.inp", "r", stdin);
  freopen("shh.out", "w", stdout);
  cin >> n;
  for (int i = 1; i <= n; ++i){
    if (check(i)) d += i;
  }
  cout << d;
}
    

#include <bits/stdc++.h>
using namespace std;
#define int long long
#define div w8rhah
const int N=1e5+5;
int div[N];
void sieve(){
	for(int i=1;i<=N-5;i++){
		for(int j=i;j<=N-5;j+=i){
			div[j]+=i;
		}
	}
}
signed main(){
	freopen("SHH.INP","r",stdin);
	freopen("SHH.OUT","w",stdout);
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	sieve();
	int n;
	cin>>n;
	int ans=0;
	for(int i=1;i<=n;i++){
		//cout<<div[i]<<"\n";
		if(div[i]-i==i){
			ans+=i;
		}
	}
	cout<<ans;
}