import java.util.HashMap;
import java.util.Map;
import java.util.Scanner;

public class Main {
	public static void main(String[] args) throws Exception {
		Scanner sc = new Scanner(System.in);
		long x = sc.nextLong();
		long a = sc.nextLong();
		long y = sc.nextLong();
		long b = sc.nextLong();
		sc.close();

		Map<Long, Integer> mx = bunkai(x);
		Map<Long, Integer> my = bunkai(y);
		for (long k : my.keySet()) {
			if (!mx.containsKey(k)) {
				System.out.println("No");
				return;
			}
			long vx = mx.get(k) * a;
			long vy = my.get(k) * b;
			if (vx < vy) {
				System.out.println("No");
				return;
			}
		}
		System.out.println("Yes");
	}

	static Map<Long, Integer> bunkai(long n) {
		Map<Long, Integer> soinsu = new HashMap<>();
		int end = (int) Math.sqrt(n);
		long d = 2;
		while (n > 1) {
			if (n % d == 0) {
				n /= d;
				soinsu.put(d, soinsu.getOrDefault(d, 0) + 1);
				end = (int) Math.sqrt(n);
			} else {
				if (d > end) {
					d = n - 1;
				}
				d++;
			}
		}
		return soinsu;
	}
}