#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
#define ll long long
#define rep(i,n) for (int i = 0; i < (n); i++)
#define coutf(f) cout << fixed << setprecision(f)
#define all(v) (v).begin(), (v).end()
#define rall(v) (v).rbegin(), (v).rend()

int main() {
	ll x, y, a, b;
	cin >> x >> a >> y >> b;
	map<ll, int> mp, mq;
	for (ll i = 2; i * i <= x; i++) {
		while (x % i == 0) {
			x /= i;
			mp[i]++;
		}
	}
	if (x != 1) mp[x]++;
	for (ll i = 2; i * i <= y; i++) {
		while (y % i == 0) {
			y /= i;
			mq[i]++;
		}
	}
	if (y != 1) mq[y]++;
	for (auto p : mp) {
		if (p.second * a < mq[p.first] * b) {
			cout << "No" << endl;
			return 0;
		}
	}
	for (auto q : mq) {
		if (mp[q.first] == 0) {
			cout << "No" << endl;
			return 0;
		}
	}
	cout << "Yes" << endl;
	return 0;
}