#include <fstream>
using namespace std;
int i,j,n,x,y,v[1000000],a[8][1000000];
int main()
{
    ifstream f("divprim.in");
    ofstream g("divprim.out");
    for(i=2;i<=1000000;i++)
    {
        if(!v[i])
        for(j=i;j<=1000000;j+=i)
        v[j]++;
        for(j=1;j<=7;j++)
        a[j][i]=a[j][i-1];
        if(v[i]<=7)
        a[v[i]][i]=i;
    }
    f>>n;
    for (i=1;i<=n;i++)
    {
        f>>x>>y;
        g<<a[y][x]<<"\n";
    }
    return 0;
}