`\color{pink}{\text{P}}``\color{red}{\text{h}}``\color{green}{\text{O}}``\color{blue}{\text{n}}``\color{balck}{\text{G}}`

#include <bits/stdc++.h>
using namespace std;
long long n,i,dem;
long long kq;
int main()
{
    cin>>n;
    for(long long i=1; i<=sqrt(n); i++)
    {
        if(n %i==0)
        {
            if(n/i==i)
            {
                dem++;
                kq+=i;
            }
            if(n/i!=i)
            {
                dem+=2;
                kq+=i+n/i;
            }
        }
    }
    if(n==kq/2) cout<<"YES";
    else cout<<"NO";
    return 0;
}

/*   /\_/\
    (= ._.)
    / >0  \>1
*/
#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

bool check (ll n)
{
  ll s = 0;
  for (ll i = 1; i <= sqrt(n); ++i)
  {
    if (n % i == 0) s += i + n / i;
  }
  ll k = sqrt(n);
  if (k * k == n) s -= k;
  return s == 2 * n;
}
ll n;
int main()  
{

  ios::sync_with_stdio(false);
  cin.tie(0);

  cin >> n;
  cout << (check(n) ? "YES" : "NO");
  return 0;
}