#include <cstdio>
#include <vector>
#include <cmath>
#define MAXN 1000000
using namespace std;
char ciur[MAXN+1];
vector <int> v[8];
int n;
inline int cbin(int mod)
{
    int start=log2(v[mod].size()),i;
    i=0;
    for(int pas=1<<start;pas;pas>>=1)
        if(i+pas<v[mod].size() && v[mod][i+pas]<=n)
            i+=pas;
    return v[mod][i]<=n? v[mod][i]:0;
}
int main()
{
    FILE *fin,*fout;
    fin=fopen("divprim.in","r");
    fout=fopen("divprim.out","w");
    int j,t,i;
    for(i=2;i<=MAXN;i++)
        if(!ciur[i])
            for(j=i;j<=MAXN;j+=i)
                ciur[j]++;
    for(i=0;i<=MAXN;i++)
        v[ciur[i]].push_back(i);
    fscanf(fin,"%d",&t);
    for(i=0;i<t;i++)
    {
        fscanf(fin,"%d%d",&n,&j);
        fprintf(fout,"%d\n",cbin(j));
    }
    fclose(fin);
    fclose(fout);
    return 0;
}