import java.util.*; import java.io.*; import java.math.*;
public class Main{
	//見なくていいよ　ここから------------------------------------------
	static class InputIterator{
		ArrayList<String> inputLine = new ArrayList<>(buf);
		int index = 0; int max; String read;
		InputIterator(){
			BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
			try{
				while((read = br.readLine()) != null){
					inputLine.addAll(Arrays.asList(read.split(" ")));
				}
			}catch(IOException e){}
			max = inputLine.size();
		}
		boolean hasNext(){return (index < max);}
		String next(){
			if(hasNext()){
				return inputLine.get(index++);
			}else{
				throw new IndexOutOfBoundsException("There is no more input");
			}
		}
	}
	//入力バッファサイズのつもり。入力点数（スペース区切りでの要素数）が100万を超える場合はバッファサイズを100万にすること
	static int buf = 1024;
	static HashMap<Integer, String> CONVSTR = new HashMap<>();
	static InputIterator ii = new InputIterator();//This class cannot be used in reactive problem.
	static PrintWriter out = new PrintWriter(System.out);
	static void flush(){out.flush();}
	static void myout(Object t){out.println(t);}
	static void myerr(Object t){System.err.print("debug:");System.err.println(t);}
	static String next(){return ii.next();}
	static boolean hasNext(){return ii.hasNext();}
	static int nextInt(){return Integer.parseInt(next());}
	static long nextLong(){return Long.parseLong(next());}
	static double nextDouble(){return Double.parseDouble(next());}
	static ArrayList<String> nextCharArray(){return myconv(next(), 0);}
	static ArrayList<String> nextStrArray(int size){
		ArrayList<String> ret = new ArrayList<>(size);
		for(int i = 0; i < size; i++){
			ret.add(next());
		}
		return ret;
	}
	static ArrayList<Integer> nextIntArray(int size){
		ArrayList<Integer> ret = new ArrayList<>(size);
		for(int i = 0; i < size; i++){
			ret.add(Integer.parseInt(next()));
		}
		return ret;
	}
	static ArrayList<Long> nextLongArray(int size){
		ArrayList<Long> ret = new ArrayList<>(size);
		for(int i = 0; i < size; i++){
			ret.add(Long.parseLong(next()));
		}
		return ret;
	}
	@SuppressWarnings("unchecked")
	static String myconv(Object list, int no){//only join
		StringBuilder sb = new StringBuilder("");
		String joinString = CONVSTR.get(no);
		if(list instanceof String[]){
			return String.join(joinString, (String[])list);
		}else if(list instanceof long[]){
			long[] tmp = (long[])list;
			if(tmp.length == 0){
				return "";
			}
			sb.append(String.valueOf(tmp[0]));
			for(int i = 1; i < tmp.length; i++){
				sb.append(joinString).append(String.valueOf(tmp[i]));
			}
			return sb.toString();
		}else if(list instanceof int[]){
			int[] tmp = (int[])list;
			if(tmp.length == 0){
				return "";
			}
			sb.append(String.valueOf(tmp[0]));
			for(int i = 1; i < tmp.length; i++){
				sb.append(joinString).append(String.valueOf(tmp[i]));
			}
			return sb.toString();
		}else if(list instanceof ArrayList){
			ArrayList tmp = (ArrayList)list;
			if(tmp.size() == 0){
				return "";
			}
			sb.append(tmp.get(0));
			for(int i = 1; i < tmp.size(); i++){
				sb.append(joinString).append(tmp.get(i));
			}
			return sb.toString();
		}else{
			throw new ClassCastException("Don't join");
		}
	}
	static ArrayList<String> myconv(String str, int no){//only split
		String splitString = CONVSTR.get(no);
		return new ArrayList<String>(Arrays.asList(str.split(splitString)));
	}
	static ArrayList<String> myconv(String str, String no){
		return new ArrayList<String>(Arrays.asList(str.split(no)));
	}
	public static void main(String[] args){
		CONVSTR.put(8, " "); CONVSTR.put(9, "\n"); CONVSTR.put(0, "");
		solve();flush();
	}
	//見なくていいよ　ここまで------------------------------------------
	//このコードをコンパイルするときは、「-encoding UTF-8」を指定すること
	static void solve(){//ここがメイン関数
		long X = nextLong();
		long A = nextLong();
		long Y = nextLong();
		long B = nextLong();
		PrimeFactorization pfx = new PrimeFactorization(X);
		PrimeFactorization pfy = new PrimeFactorization(Y);
		
		for(long key : pfy.getKeys()){
			long size = B * pfy.get(key);
			if(pfx.containsKey(key) && size <= A * pfx.get(key)){

			}else{
				myout("No");
				return;
			}
		}
		myout("Yes");
	}
	//メソッド追加エリア　ここから

static boolean isPrime(long val){
    if(val <= 1 || (val != 2 && val % 2 == 0)){
        return false;
    }else if(val == 2){
        return true;
    }
    double root = Math.floor(Math.sqrt(val));
    for(long i = 3; i <= root; i += 2){
        if(val % i == 0){
            return false;
        }
    }
    return true;
}

static class PrimeFactorization{
    HashSet<Long> primes;
    HashMap<Long, Integer> map = new HashMap<>();
    PrimeFactorization(long val){
        if(isPrime(val)){
            map.put(val, 1);
            primes = new HashSet<>(map.keySet());
            return;
        }
        long div = 2;
        while(val != 1){
            if(val % div == 0){
                int count = 2;
                while(val % (long)Math.pow(div, count) == 0){
                    count++;
                }
                if(map.containsKey(div)){
                    map.put(div, map.get(div) + (count - 1));
                }else{
                    map.put(div, count - 1);
                }
                val /= (long)Math.pow(div, count - 1);
                if(isPrime(val)){
                    if(map.containsKey(val)){
                        map.put(val, map.get(val) + 1);
                    }else{
                        map.put(val, 1);
                    }
                    break;
                }
            }else{
                div = (div == 2) ? div + 1 : div + 2;
            }
        }
        primes = new HashSet<>(map.keySet());
    }
    public int get(long K){
        return map.get(K);
    }
    public HashSet<Long> getKeys(){
        return primes;
    }
    public boolean containsKey(long K){
        return map.containsKey(K);
    }
}

	//メソッド追加エリア　ここまで
}