#include<bits/stdc++.h>
#define X 1000000
using namespace std;
int d[2*X],t,n,k,st,dr,sol,mid;
vector<int> v[15];
vector<int>::iterator it;
int main()
{
    freopen("divprim.in","r",stdin);
    freopen("divprim.out","w",stdout);
    d[1]=0;
    for(int i=2;i<=X;i++)
    {
        if(!d[i])
        {
            for(int j=i;j<=X;j+=i)
            {
                d[j]++;
            }
        }
    }
    v[0].push_back(1);
    for(int i=2;i<=X;i++)
    {
        if(d[i]<=7)
        {
            v[d[i]].push_back(i);
        }
    }
    scanf("%d",&t);
    for(int i=1;i<=t;i++)
    {
        scanf("%d%d",&n,&k);
        st=0;
        dr=v[k].size()-1;
        sol=-1;
        while(st<=dr)
        {
            mid=(st+dr)>>1;
            it=v[k].begin()+mid;
            if((*it)<=n)
            {
                sol=mid;
                st=mid+1;
            }
                else dr=mid-1;
        }
        if(sol!=(-1)) it=v[k].begin()+sol;
        if(sol==(-1)) printf("0\n");
            else printf("%d\n",(*it));
    }
    return 0;
}