#include <bits/stdc++.h>

using namespace std;

ifstream fin("divprim.in");
ofstream fout("divprim.out");

int a[1000005], nr_div[1000005];
vector<int> v;
vector<int> m[8];

int cb(int st, int dr, int x, int k)
{
    int poz = 0;
    if(x < m[k][0])
        return 0;
    if(x > m[k][m[k].size()-1])
        return m[k][m[k].size()-1];
    int mij = 0;
    while(st <= dr)
    {
        mij = (st + dr) / 2;
        if(m[k][mij] > x)
            dr = mij - 1;
        else
        {
            poz = mij;
            st = mij + 1;
        }
    }
    return m[k][poz];
}

int main()
{
    int n, i, j, q, k, exista;
    n = 1000000;
    a[2] = 1;
    for(i = 3; i <= n; i+=2)
        a[i] = 1;
    for(i = 3; i * i <= n; i+=2)
        if(a[i] == 1)
            for(j = i * i; j <= n; j+= 2 * i)
                a[j] = 0;
    for(i = 2; i <= n; i++)
        if(a[i] == 1)
            for(j = i; j <= n; j+=i)
                nr_div[j]++;
    for(i = 1; i <= 1000000; i++)
        if(nr_div[i] <= 7)
           m[nr_div[i]].push_back(i);
    fin >> q;
    for(i = 1; i <= q; i++)
    {
        fin >> n >> k;
        fout << cb(0, m[k].size()-1, n, k) << "\n";
    }
    return 0;
}