#include <bits/stdc++.h>
using namespace std;
using ll = long long;
constexpr int SQRT = 2000;
constexpr int MAX = 4000000;
bool isprime[MAX];
int d[MAX];
int main()
{
    fill(isprime, isprime + MAX, true);
    for (int i = 2; i < MAX; i++) {
        if (not isprime[i]) continue;
        for (int j = 2; i * j < MAX; j++) {
            isprime[i * j] = false;
            d[i * j] = i;
        }
    }
    ll N;
    cin >> N;
    int cnt = 0;
    for (int i = 1; i < MAX; i++) {
        if (isprime[i]) continue;
        if (isprime[i / d[i]] and i != d[i] * d[i]) {
            cnt++;
        }
        if (i == d[i] * d[i] * d[i]) {
            cnt++;
        }
        if (cnt == N) {
            cout << i << endl;
            break;
        }
    }
    return 0;
}