#include "bits/stdc++.h"
using namespace std;

#define int long long

void solve(){
    int n;
    cin >> n;

    if (n == 1) {
        cout << 1;
        return;
    }
    vector<int> primes;
    for (int i = 1e5 + 1;; i++) {
        int ok = 1;
        for (int j = 2; j * j <= i; j++) {
            if (i % j == 0) ok = 0;
            if (!ok) break;
        }
        if (ok) primes.push_back(i);
        if (primes.size() > 100) break; 
    }
    vector<int> a;
    for (int i = 0; i < primes.size(); i++) {
        for (int j = i; j < primes.size(); j++) {
            a.push_back(primes[i] * primes[j]);
        }
    }
    sort(a.begin(), a.end());
    a.erase(unique(a.begin(), a.end()), a.end());
    cout << a[n - 2];
}

signed main(){
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    
    int T = 1;
    // cin >> T;
    while(T--) solve();

    return 0;
}