#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

bool p[1000001];
vector<int> primes;

ll n;

void sieve()
{
    for (int i = 2; i <= 1000000; ++i) {
        if (!p[i]) continue;
        primes.push_back(i);
        for (int j = i + i; j <= 1000000; j += i) p[j] = false;
    }
}

bool is_prime(ll n)
{
    for (int i = 2; i * i <= n; ++i) if (n % i == 0) return false;
    return true;
}

int main()
{
    cin >> n;

    memset(p, true, sizeof(p));
    sieve();

    if (n == 1 || is_prime(n)) {
        cout << "YES" << endl;
        return 0;
    }

    for (int i = 0; i < primes.size() && (ll)primes[i] * primes[i] <= n; ++i) {
        if (n % primes[i] == 0) {
            cout << "YES" << endl;
            return 0;
        }
    }

    cout << "NO" << endl;
}