#include<fstream>
#define DIM 1000005
using namespace std;
int t, k, n, i, j;
int c[DIM], f[DIM];
int d[DIM][8];
ifstream fin("divprim.in");
ofstream fout("divprim.out");
int main(){
    for(i = 2; i <= 1000000; i++){
        if(c[i] == 0){
            f[i] = 1;
            for(j = i + i; j <= 1000000; j+= i){
                c[j] = 1;
                f[j]++;
            }
        }
    }
    for(i = 2; i <= 1000000; i++){
        for(j = 1; j <= 7; j++){
            if(f[i] == j){
                d[i][j] = i;
            }
            else{
                d[i][j] = d[i - 1][j];
            }
        }
    }
    fin>> t;
    for(i = 1; i <= t; i++){
        fin>> n >> k;
        fout<< d[n][k] <<"\n";
    }
    return 0;
}