#include <bits/stdc++.h>
using namespace std;
const int MAXN = 1e5 + 5;
const long long INF = 1e15 + 5;
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  long long N, M, K;
  cin >> N >> M >> K;
  auto check = [&](long long m) {
    long long ans = 0;
    for (int i = (1); i < int(N + 1); i++) ans += min((m - 1) / i, M);
    return ans;
  };
  long long l = 0, r = INF, mid;
  while (r - l > 1) {
    mid = (r - l) / 2 + l;
    if (check(mid) < K)
      l = mid;
    else
      r = mid;
  }
  cout << l << endl;
  return 0;
}
