#include <bits/stdc++.h>
using namespace std;
using Int = long long;
constexpr static int mod = 1e9 + 7;
constexpr static int inf = (1 << 30) - 1;
constexpr static Int infll = (1LL << 61) - 1;
int Competitive_Programming = (ios_base::sync_with_stdio(false), cin.tie(nullptr), cout << fixed << setprecision(15), 0);
#pragma GCC optimize("Ofast", "unroll-loops", "omit-frame-pointer", "inline")
#pragma GCC option("arch=native", "tune=native", "no-zero-upper")
#pragma GCC target("avx2")

map<Int, Int> primes(Int n)
{
    map<Int, Int> mp;

    for (Int i = 2; i * i <= n; i++)
    {
        while (n % i == 0)
            n /= i, mp[i]++;
    }

    if (n > 1)
        mp[n]++;

    return mp;
}

int main()
{
    Int x, a, y, b;
    cin >> x >> a >> y >> b;
    auto px = primes(x), py = primes(y);

    for (auto &&[k, v] : py)
    {

        if (px[k] * a < v * b)
        {
            cout << "No\n";
            return 0;
        }
    }

    cout << "Yes\n";
}