#include <cstdio>
#define L 1000000
using namespace std;
int i,j,n,x,y,v[L],a[8][L];
int main()
{
    freopen("divprim.in","r",stdin);
    freopen("divprim.out","w",stdout);
    for(i=2;i<=L;i++)
    {
        if(!v[i])
        {
            for(j=i;j<=L;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;
    }
    scanf("%d",&n);
    for(i=1;i<=n;++i)
    {
        scanf("%d%d",&x,&y);
        printf("%d\n",a[y][x]);
    }
    fclose(stdin);
    fclose(stdout);
    return 0;
}