import java.io.*;
import java.util.*;

public class Main {
    public static void main(String[] args) throws Exception {
        Scanner sc = new Scanner();
        long x = sc.nextLong();
        long a = sc.nextLong();
        long y = sc.nextLong();
        long b = sc.nextLong();
        HashMap<Long, Integer> countsX = getCount(x);
        HashMap<Long, Integer> countsY = getCount(y);
        for (long z : countsY.keySet()) {
            if (!countsX.containsKey(z) || countsX.get(z) * a < countsY.get(z) * b) {
                System.out.println("No");
                return;
            }
        }
        System.out.println("Yes");
    }
    
    static HashMap<Long, Integer> getCount(long x) {
        HashMap<Long, Integer> ans = new HashMap<>();
        for (long i = 2; i <= Math.sqrt(x); i++) {
            while (x % i == 0) {
                ans.put(i, ans.getOrDefault(i, 0) + 1);
                x /= i;
            }
        }
        if (x > 1) {
            ans.put(x, ans.getOrDefault(x, 0) + 1);
        }
        return ans;
    }
}

class Scanner {
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    StringTokenizer st = new StringTokenizer("");
    
    public Scanner() throws Exception {
        
    }
    
    public int nextInt() throws Exception {
        return Integer.parseInt(next());
    }
    
    public long nextLong() throws Exception {
        return Long.parseLong(next());
    }
    
    public double nextDouble() throws Exception {
        return Double.parseDouble(next());
    }
    
    public String next() throws Exception {
        while (!st.hasMoreTokens()) {
            st = new StringTokenizer(br.readLine());
        }
        return st.nextToken();
    }
}