#include <bits/stdc++.h>
using namespace std;
typedef long long int ll;
typedef pair<ll,ll> P;
typedef vector<ll> VI;
typedef vector<VI> VVI;
#define REP(i,n) for(ll i=0;i<(n);i++)
#define ALL(v) v.begin(),v.end()
template<typename T> bool chmax(T &x, const T &y) {return (x<y)?(x=y,true):false;};
template<typename T> bool chmin(T &x, const T &y) {return (x>y)?(x=y,true):false;};
constexpr ll MOD=998244353;
constexpr ll INF=2e18;

int main(){
    ll x, a, y, b;
    cin >> x >> a >> y >> b;
    ll cnt=0;
    while(x%y==0){
        x/=y;
        cnt++;
    }
    if(a*cnt>=b)
        cout << "Yes" << endl;
    else
        cout << "No" << endl;
}