#include <vector>
#include <iostream>
using namespace std;

vector<pair<long long, int> > factorize(long long n) {
    vector<pair<long long, int> > ret;
    for (long long p = 2; p * p <= n; p++) {
        if (n % p == 0) {
            int e = 0;
            while (n % p == 0) { e++; n /= p; }
            ret.emplace_back(p, e);
        }
    }
    if (n > 1) ret.emplace_back(n, 1);
    return ret;
}

int main() {
    long long x, a, y, b; cin >> x >> a >> y >> b;
    vector<pair<long long, int> > fx = factorize(x), fy = factorize(y);
    for (auto [p, e] : fy) {
        bool ok = false;
        for (auto [q, d] : fx) {
            if (p == q) {
                if (b * e <= a * d) ok = true;
                else break;
            }
        }
        if (!ok) { cout << "No\n"; return 0; }
    }
    cout << "Yes\n";
}