#include <bits/stdc++.h>
using namespace std;
long long n, m, k;
long long ok(long long x) {
  long long res = 0;
  x--;
  for (int i = 1; i <= n; i++) res += min(m, x / i);
  return res;
}
int main() {
  scanf("%I64d %I64d %I64d", &n, &m, &k);
  long long l = 0, r = 1e18;
  while (r - l > 1) {
    long long mid = (l + r) >> 1;
    if (ok(mid) < k)
      l = mid;
    else
      r = mid;
  }
  printf("%I64d", l);
  return 0;
}
