#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(1e5 + 1);
  for (int i = 1; i <= 1e5; ++i) for (int j = 1; i * j <= 1e5; ++j) d[i * j].push_back(i);
  vector<vector<int>> nv(n);
  for (int i = 0; i < n; ++i)
  {
    int siz = d[a[i]].size();
    nv[i].push_back(b[i]);
    for (int j = 0; j < siz; ++j)
    {
      int tmp = (b[i] + d[a[i]][j] - 1) / d[a[i]][j] * d[a[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;
}