#include <iostream>
#include <vector>
#include <cmath>
#include <map>
#include <set>
#include <iomanip>
#include <queue>
#include <algorithm>
#include <numeric>
#include <deque>

using namespace std;
using ll = long long;


map<ll, ll> prime_factor(ll n){
    ll m = n;
    map<ll, ll> prime;

    if (n % 2 == 0){
        while(n % 2 == 0){
            prime[2]++;
            n /= 2;
        }
    }

    for (ll i = 3; i*i <= m; i+=2){
        if (n % i == 0){
            while(n % i == 0){
                prime[i]++;
                n /= i;
            }
        }
    }

    if (n != 1){
        prime[n]++;
    }

    return prime;
}

int main(){

    ll X, A, Y, B;
    cin >> X >> A >> Y >> B;
    map<ll, ll> xp, yp;
    xp = prime_factor(X);
    yp = prime_factor(Y);
    for (auto [p, e] : yp){
        if (xp[p] * A < e * B){
            cout << "No" << endl;
            return 0;
        }
    }

    cout << "Yes" << endl;

    return 0;
}