#include <iostream>
#include <algorithm>
#include <vector>
using namespace std;
#define LL long long
#define mp make_pair

const int N = 1e5 + 5;
int T, n;
bool used[N];

int main(){
    ios::sync_with_stdio(false);
    cin.tie(0), cout.tie(0);

    cin >> T;
    while (T--){
        cin >> n;
        for (int i = 1; i <= n; i++){
            used[i] = false;
        }

        vector<pair<int, int>> ans;
        for (int i = n; i > 1; i--){
            if (used[i]){
                continue;
            }
            int res = 0;
            for (int j = i + i; j <= n; j += i){
                if (!used[j]){
                    res = j;
                }
            }
            if (res){
                used[i] = used[res] = true;
                ans.push_back(mp(i, res));
            }
        }

        if (ans.size() == 0){
            cout << ans.size() << endl;
        }else{
            cout << ans.size() << ' ';
            for (int i = 0; i < ans.size(); i++){
                cout << ans[i].first << ' ' << ans[i].second << " \n"[i == ans.size() - 1];
            }
        }
    }

    return 0;
}