#include <iostream>
#include <fstream>
#include <vector>
using namespace std;

const int MAXN = 1000000;
int divp[MAXN + 1];
int ans[8][MAXN + 1];
vector<int> L[8];

int main()
{
    ifstream f("divprim.in");
    ofstream g("divprim.out");

    for (int i = 2; i <= MAXN; i++)
    {
        if (divp[i] == 0)
        {
            for (int j = i; j <= MAXN; j += i)
            {
                divp[j]++;
            }
        }
    }
    //L[i] = lista numerelor care au i divizori primi (numerele sunt sortate crescator)
    for(int i = 2; i <= MAXN; i++) {
        L[divp[i]].push_back(i);
    }

    int T;
    f >> T;

    for (int t = 0; t < T; t++)
    {
        int N, K;
        f >> N >> K;
        int st = 0;
        int dr = L[K].size();
        int sol = 0;
        while(st <= dr) {
            int mid = (st + dr) / 2;
            if(L[K][mid] <= N) {
                sol = L[K][mid];
                st = mid + 1;
            } else {
                dr = mid - 1;
            }
        }
        g << sol << '\n';
        //g << ans[K][N] << '\n';
    }

    return 0;
}