#include <bits/stdc++.h>
using namespace std;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
int dx[8] = {1, -1, 0, 0, -1, -1, 1, 1};
int dy[8] = {0, 0, -1, 1, -1, 1, -1, 1};
vector<int> adj[300010], val(300010, 1), vis(300010, 0), dis1(300010, 0),
    dis2(300010, 0);
int myrandom(int i) { return std::rand() % i; }
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  long long n, m, k;
  cin >> n >> m >> k;
  long long lo = 0, hi = n * m + 1;
  while (hi - lo > 1) {
    long long mid = (lo + hi) / 2;
    long long cnt = 0;
    for (int i = 1; i <= n; i++) {
      cnt = cnt + min(mid / i, m);
    }
    if (cnt < k) {
      lo = mid;
    } else {
      hi = mid;
    }
  }
  cout << hi << '\n';
}
