import java.util.Scanner;

public class Yukicoder36 {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		long n = sc.nextLong();
		for (long i = 2; i < Math.sqrt(n); i++) {
			if (n % i * i == 0) {
				System.out.println("YES");
				return;
			}
		}
		System.out.println("NO");
	}
}