#include <fstream>

using namespace std;
ifstream fin("divprim.in");
ofstream fout("divprim.out");
int c[1000001];
long i,j,m[1000001][8],a,b,n;
int main()
{
    for(i=2;i<=1000001;i++)
    {
        if(c[i]==0)
            for(j=i;j<=1000001;j=j+i)
                c[j]++;
        for(j=0;j<=7;j++)
            m[i][j]=m[i-1][j];
        if(c[i]<=7) m[i][c[i]]=i;
    }
    fin>>n;
    for(i=1;i<=n;i++)
    {
        fin>>a>>b;
        fout<<m[a][b]<<'\n';
    }
    return 0;
}