quad

#include <iostream>
using namespace std;

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
    long int spos = 0;
    long long int w, h, s;
    cin >> h >> w >> s;
    if (s > h * w) cout << 0;
    else if (s == h * w) cout << 1;
    else
    {
        for (long long int i = 1; i <= s; ++i) {
            long long int dr = s / i;
            if (s % i == 0) {
                 long int vd = h + 1 - dr;
                 long int vsh = w + 1 - i;
                if (vd * vsh >= 0) spos += vd * vsh;


            }
        }
        cout << spos;



    }
}