#include <bits/stdc++.h>
using namespace std;
const int N = 1e5 + 40;
void solve() {
  long long int n, m, k;
  cin >> n >> m >> k;
  long long int beg = 1, end = n * m;
  long long int fa;
  while (beg <= end) {
    long long int mid = (beg + end) / 2;
    long long int cnt = 0;
    for (int i = 1; i <= n; i++) {
      cnt += min(m, mid / i);
    }
    if (cnt >= k) {
      end = mid - 1;
      fa = mid;
    } else
      beg = mid + 1;
  }
  cout << fa << '\n';
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  int T = 1;
  while (T--) {
    solve();
    if (T) {
      char c;
    }
  }
}
