#include <bits/stdc++.h>
using namespace std;
using ll = long long;
const ll INF = 1ll << 60;
#define REP(i, n) for(ll i =0; i < ll(n); i++)
template <class T> using V = vector<T>;
template <class A, class B>
bool chmax(A& a, B b) { return a<b && (a=b, true); }
template <class A, class B>
bool chmin(A& a, B b) { return b<a && (a=b, true); }

void testcase() {
  ll n, w; cin >> n >> w;
  V<ll> x(n), y(n);
  REP(i, n) cin >> x[i];
  REP(i, n) cin >> y[i];
  V<ll> tbl(200001);
  REP(i, n) {
    for(ll d = 1; d*d <= x[i]; d++) {
      if(x[i]%d) continue;
      tbl[d] += y[i];
      if(d*d < x[i]) tbl[x[i]/d] += y[i];
    }
  }
  ll ans = 0;
  REP(i, 200001) {
    if(i >= w) chmax(ans, tbl[i]);
  }
  cout << ans << '\n';
}

int main() {
  cin.tie(0)->sync_with_stdio(0);
  testcase();
}