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

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

vector<int> v[9];

int ciur[1000100], t, n, k;

int main()
{
    for(int i=2;i<=1000000;++i)
    {
        if(ciur[i]==0)
        {
            for(int j=i;j<=1000000;j+=i) ciur[j]++;
        }
    }
    for(int i=1;i<=1000000;++i) v[ciur[i]].push_back(i);
    fin>>t;
    while(t--)
    {
       fin>>n>>k;
       int st=0, dr=v[k].size()-1, sol=0;
       while(st<=dr)
       {
           int mid=(st+dr)/2;
           if(v[k][mid]<=n) st=mid+1, sol=v[k][mid];
           else dr=mid-1;
       }
       fout<<sol<<"\n";
    }
    return 0;
}