#include<cstdio>
int i,j,n,k,t,div[1000001],d,pp,a[1000001][9];
int main(){
    freopen("divprim.in","r",stdin);
    freopen("divprim.out","w",stdout);


    d=2;
    while(d<=1000001){

        for(i=d;i<=1000001;i+=d)
            div[i]++;
        d++;
        while(div[d]!=0)
            d++;
    }
    for(i=1;i<=1000000;i++)
        a[i][div[i]]=i;
    for(i=1;i<=1000000;i++)
        for(j=1;j<=7;j++)
            if(a[i-1][j]>a[i][j])
                a[i][j]=a[i-1][j];


    scanf("%d",&t);
    for(i=1;i<=t;i++){
        scanf("%d%d",&n,&k);
       printf("%d\n",a[n][k]);
    }
    return 0;
}