\begin{array}{c} \color{#db1616}{\texttt{#Khoadang09}} \end{array}
`@`$\texttt{C++: }$

#include <bits/stdc++.h>
#define int long long
#define buff ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);
// #pragma GCC optimize("O2")
// #pragma GCC optimize("Ofast")
// K nên dùng
using namespace std;
bool check_prime(int n){
    if (n==2||n==3) return true;
    if (n<2||n%2==0||n%3==0) return false;
    for (int i=5;i*i<=n;i+=6)
        if (n%i==0||n%(i+2)==0)
            return false;
    return true;
}
signed main() {
    buff;
    int n; cin >> n;
    if (check_prime(n)) cout << "YES";
        else cout << "NO";
    return 0;
}

#include <iostream>
#include <cmath>
using namespace std;
bool ok(long long n) {
if (n<=1) 
return false;
if (n<=3) 
return true;
if (n%2==0||n%3==0) 
return false;
for (long long i=5;i*i<=n;i+=6) {
if (n%i==0||n%(i+2)==0) 
return false;
}
return true;
}
int main() {
long long n;
cin>>n;
if (ok(n)) 
cout<<"YES"<<endl;
else cout<<"NO"<<endl;
return 0;
}