#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
using ll = long long;
using mint = modint998244353;
using vi = vector<int>;
using vvi = vector<vi>;
using vvvi = vector<vvi>;
using vll = vector<ll>;
using vvll = vector<vll>;
using vvvll = vector<vvll>;
using vmi = vector<mint>;
using vvmi = vector<vmi>;
using vvvmi = vector<vvmi>;
#define all(a) (a).begin(), (a).end()
#define rep2(i, m, n) for (int i = (m); i < (n); ++i)
#define rep(i, n) rep2(i, 0, n)
#define drep2(i, m, n) for (int i = (m)-1; i >= (n); --i)
#define drep(i, n) drep2(i, n, 0)

void solve(){
    
}

int main(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    vvi vv(200010);
    rep2(i, 1, 200010){
        for(int j = i; j < 200010; j += i)vv[j].push_back(i);
    }
    int n, w; cin >> n >> w;
    vi x(n); rep(i, n)cin >> x[i];
    vll y(n); rep(i, n)cin >> y[i];
    vll z(200010, 0);
    rep(i, n){
        for(auto j : vv[x[i]])z[j] += y[i];
    }
    ll ans = 0;
    rep2(i, w, 200010)ans = max(ans, z[i]);
    cout << ans << endl;
    return 0;
}