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

class Program
{
    static int NN => int.Parse(ReadLine());
    static int[] NList => ReadLine().Split().Select(int.Parse).ToArray();
    static int[][] NArr(long n) => Enumerable.Repeat(0, (int)n).Select(_ => NList).ToArray();
    static int[] NMi => ReadLine().Split().Select(c => int.Parse(c) - 1).ToArray();
    static int[][] NMap(int n) => Enumerable.Repeat(0, n).Select(_ => NMi).ToArray();
    static string[] SList(long n) => Enumerable.Repeat(0, (int)n).Select(_ => ReadLine()).ToArray();
    public static void Main()
    {
        Solve();
    }
    static void Solve()
    {
        var t = NN;
        var ans = new int[t];
        for (var u = 0; u < t; ++u)
        {
            var c = NList;
            var (n, k) = (c[0], c[1]);
            ans[u] = Prod(n, k);
        }
        WriteLine(string.Join("\n", ans));
    }
    static int Prod(int n, int k)
    {
        var tmp = n;
        while (tmp > k)
        {
            var flg = true;
            for (var i = 1; i * i <= n && i <= k; ++i)
            {
                if (tmp % i == 0 && tmp / i <= k)
                {
                    flg = false;
                    break;
                }
            }
            if (flg) return tmp;
            --tmp;
        }
        return -1;
    }
}