#include<bits/stdc++.h>
#define ll long long
using namespace std;
ll n, m, k;
bool check(ll x)
{
    ll cnt = 0;
    for(int i = 1; i <= n; i++)
    {
       cnt+=min(m, x / i);
    }
    return cnt >= k;
}
int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    freopen("cau4.INP", "r", stdin);
    freopen("cau4.OUT", "w", stdout);    
    cin >> n >> m >> k;
    ll l = 1, r = n * m, res = 0;
    while(l <= r)
    {
        ll mid = (l + r) / 2;
        if(check(mid))
        {
            res = mid;
            r = mid - 1;
        }
        else
            l = mid + 1;
    }
    cout << res;
}