#include <bits/stdc++.h>
#define fi first
#define se second

using std::cin;
using std::cout;
using std::map;
using std::pair;
using ll = long long;

map<ll, int> factorize(ll n) {
	map<ll, int> mp;
	for (ll i = 2; i * i <= n; ++i) {
		if (n % i) continue;
		while (n % i == 0) {
			n /= i;
			mp[i]++;
		}
	}
	if (n != 1) mp[n] = 1;
	return mp;
}

int main() {
	ll x, a, y, b;
	cin >> x >> a >> y >> b;
	
	auto f = factorize(x);
	auto g = factorize(y);
	
	bool ok = all_of(g.begin(), g.end(), [&](pair<ll, int> p) {
		return f[p.fi] * a >= p.se * b;
	});
	
	puts(ok ? "Yes" : "No");
	
	return 0;
}