#include <bits/stdc++.h>
using namespace std;
long long n, m, k, a, b, mid;
long long P(long long u) {
  long long s = 0;
  for (int i = 1; i <= n; i++) s += min(m, u / i);
  return s;
}
int main() {
  cin.tie(0);
  ios_base::sync_with_stdio(0);
  cin >> n >> m >> k;
  a = 1;
  b = n * m;
  while (a < b) {
    mid = (a + b) / 2;
    if (P(mid) > k)
      b = mid - 1;
    else if (P(mid) < k)
      a = mid + 1;
    else {
      while (P(mid - 1) == k) mid--;
      cout << mid;
      return 0;
    }
  }
  if (P(a) < k) a++;
  cout << a;
  return 0;
}
