#pragma GCC optimize("Ofast")
#include <iostream>
#include <vector>
#include <algorithm>
#include <queue>

using namespace std;

int main()
{
  ios::sync_with_stdio(false);
  cin.tie(nullptr);
  int n;
  long long k;
  cin >> n >> k;
  vector<long long> a(n), b(n);
  for (int i = 0; i < n; ++i) cin >> a[i];
  for (int i = 0; i < n; ++i) cin >> b[i];
  vector<vector<int>> d(n);
  {
    vector<int> check(1e5 + 1), p(1e5 + 1);
    vector<vector<int>> id(1e5 + 1);
    for (int i = 0; i < n; ++i)
    {
      check[a[i]] = 1;
      id[a[i]].push_back(i);
    }
    for (int i = 1; i <= 1e5; ++i)
    {
      if (!check[i]) continue;
      vector<int> tmp;
      for (int j = 1; j * j <= i; ++j)
      {
        if (i % j == 0)
        {
          tmp.push_back(j);
          tmp.push_back(i / j);
        }
      }
      sort(tmp.begin(), tmp.end());
      tmp.erase(unique(tmp.begin(), tmp.end()), tmp.end());
      for (auto v : id[i]) d[v] = tmp;
    }
  }
  vector<vector<int>> nv(n);
  for (int i = 0; i < n; ++i)
  {
    int siz = d[i].size();
    nv[i].push_back(b[i]);
    for (int j = 0; j < siz; ++j)
    {
      int tmp = (b[i] + d[i][j] - 1) / d[i][j] * d[i][j];
      while (!nv[i].empty() && nv[i].back() >= tmp) nv[i].pop_back();
      nv[i].push_back(tmp);
    }
    reverse(nv[i].begin(), nv[i].end());
    nv[i].pop_back();
  }
  priority_queue<pair<int, int>> pq;
  for (int i = 0; i < n; ++i)
  {
    int g = __gcd(a[i], b[i]);
    pq.push({-g, i});
  }
  while (!pq.empty())
  {
    auto [gv, id] = pq.top();
    pq.pop();
    if (nv[id].empty()) continue;
    int nb = nv[id].back();
    nv[id].pop_back();
    int c = nb - b[id];
    if (k < c) break;
    b[id] = nb;
    k -= c;
    pq.push({-__gcd(a[id], b[id]), id});
  }
  long long ans = 1e9;
  for (int i = 0; i < n; ++i) ans = min(ans, __gcd(a[i], b[i]));
  cout << ans << endl;
}