#include <map>
#include <cmath>
#include <string>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;
map<long long, int> prime_factorize(long long N) {
	map<long long, int> d;
	for (int i = 2; 1LL * i * i <= N; ++i) {
		if (N % i == 0) {
			int cnt = 0;
			while (N % i == 0) {
				++cnt;
				N /= i;
			}
			d[i] += cnt;
		}
	}
	if (N > 1) {
		d[N] += 1;
	}
	return d;
}
int main() {
	long long X, A, Y, B;
	cin >> X >> A >> Y >> B;
	map<long long, int> dx = prime_factorize(X);
	map<long long, int> dy = prime_factorize(Y);
	bool flag = true;
	for (pair<long long, int> i : dy) {
		if (dx[i.first] * A < dy[i.first] * B) {
			flag = false;
			break;
		}
	}
	cout << (flag ? "Yes" : "No") << endl;
	return 0;
}