using System;
using static System.Console;
using System.Linq;
using System.Collections.Generic;

class Program
{
    static int NN => int.Parse(ReadLine());
    static long[] NList => ReadLine().Split().Select(long.Parse).ToArray();
    public static void Main()
    {
        Solve();
    }
    static void Solve()
    {
        var c = NList;
        var (n, k) = (c[0], c[1]);
        var a = NList;
        var ans = 1L;
        for (var i = 0; i < n; ++i)
        {
            foreach (var p in PList(a[i]))
            {
                var sum = 0L;
                for (var j = 0; j < n; ++j)
                {
                    sum += Math.Min(a[j] % p, p - a[j] % p);
                }
                if (sum <= k) ans = Math.Max(ans, p);
            }
        }
        WriteLine(ans);
    }
    static List<long> PList(long n)
    {
        var ans = new List<long>();
        for (var i = 1L; i * i <= n; ++i)
        {
            if (n % i == 0)
            {
                ans.Add(i);
                if (i * i < n) ans.Add(n / i);
            }
        }
        return ans;
    }
}