#include<fstream>
using namespace std;
const int W=1000001;
ifstream f("divprim.in");
ofstream g("divprim.out");
int a[W][9],div[W];
int main()
{
    int i,j,n,k,x,d,pp;
    d=2;
    while(d<=W){

        for(i=d;i<=W;i+=d)
            div[i]++;
        d++;
        while(div[d]!=0)
            d++;
    }
    for(i=1;i<=W;i++)
        a[i][div[i]]=i;
    for(i=1;i<=W;i++)
        for(j=1;j<=7;j++)
            if(a[i-1][j]>a[i][j])
                a[i][j]=a[i-1][j];
    f>>n;
    for(i=1;i<=n;i++){
        f>>x>>k;
        g<<a[x][k]<<"\n";
    }
    return 0;
}