#include <bits/stdc++.h>
using namespace std;
template<typename T>
map<T, T> divide(T n){//素因数分解
    map<T, T> res;
    for(T i = 2; i * i <= n; i++){
        while(n % i == 0){
            res[i]++;
            n /= i;
        }
    }
    if(n != 1) res[n] = 1;
    return res;
}
int main(){
    long long N, K, M;
    cin >> N >> K >> M;
    map<long long, long long> m = divide(M);
    map<long long, long long> cnt;
    for(auto [a, b] : m){
        long long t = a;
        while(t <= N){
            cnt[a] += N / t;
            if(t <= N / a) t *= a;
            else break;
        }
        t = a;
        while(t <= K){
            cnt[a] -= K / t;
            if(t <= K / a) t *= a;
            else break;
        }
        t = a;
        while(t <= N - K){
            cnt[a] -= (N - K) / t;
            if(t <= (N - K) / a) t *= a;
            else break;
        }
    }
    long long ans = N;
    for(auto [a, b] : m){
        ans = min(ans, cnt[a] / b);
    }
    cout << ans << endl;
}