//No.36 素数が嫌い！

import java.util.*;
import java.io.*;
import static java.util.Arrays.*;
import static java.lang.Math.*;

public class No36 {
    
    static final Scanner sc = new Scanner(System.in);
    static final PrintWriter out = new PrintWriter(System.out,false);

    static void solve() {
        long n = sc.nextLong();
        if (n == 1) {
            out.println("NO");
            return;
        }
        int[] primes = sieveOfEratosthenes((int)sqrt(n));
        int cnt = 0;
        for (int i=0; i<primes.length; i++) {

            if (n%primes[i] == 0) cnt++;
            if (cnt == 2 || n%((long)primes[i]*primes[i]) == 0) {
                out.println("YES");
                return;
            }
        }
        out.println("NO");
    }

    static int[] sieveOfEratosthenes(int n) {
        if (n < 2) return null;
        boolean[] isPrime = new boolean[n];
        fill(isPrime,true);
        int[] res = new int[n];
        int ptr = 0;
        isPrime[0] = isPrime[1] = false;
        for (int i=2; i<n; i++) {
            if (isPrime[i]) {
                res[ptr++] = i;
                for (int j=i+i; j<n; j+=i) isPrime[j] = false;
            }
        }
        return Arrays.copyOfRange(res,0,ptr);
    }

    public static void main(String[] args) {
        long start = System.currentTimeMillis();

        solve();
        out.flush();

        long end = System.currentTimeMillis();
        //trace(end-start + "ms");
        sc.close();
    }

    static void trace(Object... o) { System.out.println(deepToString(o));}
}