#include <cstdio>
#include <vector>
#include <queue>
#include <stack>
#include <list>
#include <set>
#include <algorithm>
#include <utility>
#include <string>
#include <functional>
#include <sstream>
#include <fstream>
#include <iostream>
using namespace std;
#define FOR(i,a,b) for (i=a;i<=b;i++)
#define fori(it,v) for (it=(v).begin();it!=(v).end();it++)
#define pb push_back
#define mp make_pair
#define fs first
#define ss second
#define all(c) c.begin(),c.end()
#define pf push_front
#define popb pop_back
#define popf pop_front
vector<int>a[8];
int nrdiv[1000005];
void ciur(int n)
{
	char p[1000006]={0};
	int i,j;
	for (i=2;i<=n;i++)
		if (!p[i])
		{
			for (j=i;j<=n;j+=i)
				p[j]+=1;
		}
	for (i=2;i<=n;i++)
	{
		a[p[i]].pb(i);
		if (i<=10)
			printf("%d %d\n",i,p[i]);
	}

}
int main()
{
	FILE *in,*out;
	int i,j,nr,x,t,k,n;
	in=fopen("divprim.in","r");
	out=fopen("divprim.out","w");
	for (i=1;i<=7;i++)
	{
		a[i].pb(0);
	}
	a[0].pb(1);
	ciur(1000000);
	fscanf(in,"%d",&t);
	vector<int>::iterator it;
	for (;t;t--)
	{
		fscanf(in,"%d%d",&n,&k);
		it=lower_bound(all(a[k]),n);
		if (*it!=n)
			it--;
		fprintf(out,"%d\n",*it);
	}
	fclose(in);
	fclose(out);
	return 0;
}