#include <bits/stdc++.h>
#define rep(i,n) for(int i = 0; i < (n); i++)
using namespace std;
typedef long long ll;

vector<pair<long long, long long>> prime_factorize(long long N){
    vector<pair<long long, long long>> res;
    for(long long a = 2; a * a <= N; ++a){
        if(N % a != 0) continue;
        long long ex = 0;
        while(N % a == 0) ++ex, N /= a;
        res.push_back({a,ex});
    }
    if(N != 1) res.push_back({N,1});
    return res;
}

int main(){
    cin.tie(0);
    ios::sync_with_stdio(0);
    
    // [N!] / [K! (N-K)!]
    ll N,K,M; cin >> N >> K >> M;
    auto f = [](ll X, ll p) {
        ll res = 0, m = p;
        do {
            res += X / m;
            m *= p;
        } while(2 <= m && m <= X);
        return res;
    };
    auto pf = prime_factorize(M);
    ll ans = 8e18;
    for(auto [p, e] : pf) {
        ll x = 0;
        x += f(N, p);
        x -= f(K, p);
        x -= f(N - K, p);
        x /= e;
        ans = min(ans, x);
    }

    cout << ans << endl;
}