#include <bits/stdc++.h>
using namespace std;

long long x, y, a, b;
bool g = 1;
bool f[1000000];
set<long long> p = { 2 };
map<long long, int> xp, yp;

int main()
{
	cin >> x >> a >> y >> b;

	for (long long i = 3; i < 1000000; i += 2) {
		if (!f[i]) {
			p.insert(i);

			for (long long j = i * i; j < 1000000; j += i * 2) {
				f[j] = 1;
			}
		}
	}

	for (long long j : p) {
		if (x % j == 0) {
			while (x % j == 0) {
				xp[j]++;
				x /= j;
			}
		}

		if (y % j == 0) {
			while (y % j == 0) {
				yp[j]++;
				y /= j;
			}
		}
	}

	if (x > 1)
		xp[x]++;

	if (y > 1)
		yp[y]++;

	for (auto j : yp) {
		if (xp[j.first] * a < j.second * b)
			g = 0;
	}

	if (g)
		cout << "Yes" << endl;
	else
		cout << "No" << endl;
	
}