#include <iostream>
#include <vector>
using namespace std;
int main()
{
    long long x, y, a, b;
    cin >> x >> a >> y >> b;
    if (y == 1) {
        cout << "Yes" << endl;
        return 0;
    }
    if (x == y && a >= b) {
        cout << "Yes" << endl;
        return 0;
    }
    long long x_ = x;
    long long y_ = y;
    vector<long long> cnt_x(1000000, 0), cnt_y(1000000, 0);
    for (long long i = 2; i < 1000000; i++) {
        while (x % i == 0) {
            x /= i;
            cnt_x[i]++;
        }
    }
    for (long long i = 2; i < 1000000; i++) {
        while (y % i == 0) {
            y /= i;
            cnt_y[i]++;
        }
    }
    if (x % y != 0) {
        cout << "No" << endl;
        return 0;
    }
    for (int i = 2; i < 1000000; i++) {
        if (cnt_x[i] * a < cnt_y[i] * b) {
            cout << "No" << endl;
            //cout << i << endl;
            return 0;
        }
    }
    if (y != 1 && a < b) {
        cout << "No" << endl;
        return 0;
    }
    cout << "Yes" << endl;
}