#include <bits/stdc++.h>
//#include <atcoder/all>
using namespace std;
//using namespace atcoder;
using ll = long long;
using ull = unsigned long long;
using ld = long double;
//using mint = modint998244353;
vector<ll> calc(ll x){
    vector<ll> ret(0);
    for(ll i = 1; i*i <= x; i++){
        if(x % i == 0){
            ret.push_back(i);
            if(i*i < x)ret.push_back(x/i);
        }
    }
    return ret;
}

int main(){
    cin.tie(nullptr);
    ios_base::sync_with_stdio(false);

    ll n,w;
    cin >> n >> w;

    vector<ll> x(n,0);
    vector<ll> y(n,0);
    for(ll i = 0; i < n; i++){
        cin >> x[i];
    }
    for(ll i = 0; i < n; i++){
        cin >> y[i];
    }

    unordered_map<ll,ll> dp;
    vector<vector<ll>> yaku(n,vector<ll>(0));
    for(ll i = 0; i < n; i++){
        yaku[i] = calc(x[i]);

        for(ll t : yaku[i]){
            dp[t] += y[i];
        }
    }

    ll ans = 0;
    for(ll i = w; i <= 200000; i++){
        ans = max(ans,dp[i]);
    }
    
    cout << ans << '\n';

}