#include <bits/stdc++.h>
using namespace std;
const long long MOD1 = 1000000007;
const long long MOD2 = 998244353;
typedef long long ll;
//typedef int ll;
typedef pair<ll, ll> P;
const long long INF = 1e9;
template <typename T>
void input_arr(vector<T>& A, ll N) {
	for (ll i = 0; i < N; i++) {
		cin >> A[i];
	}
}
template <typename T, typename Q>
void input_arr(vector<pair<T, Q>>& A, ll N) {
	for (ll i = 0; i < N; i++) {
		cin >> A[i].first >> A[i].second;
	}
}
template <typename T>
void input_arr(vector<vector<T>>& A, ll H, ll W) {
	for (ll i = 0; i < H; i++) {
		for (ll j = 0; j < W; j++) {
			cin >> A[i][j];
		}
	}
}
vector<P> prime_factorization(ll N) {
    vector<P>A;
    ll tmp = N;
    for (ll i = 2; i * i <= N; i++) {
        if (tmp % i == 0) {
            A.push_back({ i, 0 });
            while (tmp % i == 0) {
                A.back().second++;
                tmp /= i;
            }
        }
    }
    if (tmp != 1) A.push_back({ tmp, 1 });
    return A;
}
int main() {
    ll N, K, M; cin >> N >> K >> M;
    vector<P>Q = prime_factorization(M);
    vector<ll>A;
    for (ll i = 0; i < Q.size(); i++) {
        ll sum = 0, sum2 = 0, sum3 = 0;
        ll m = Q[i].first;
        while (N / m != 0) {
            sum += N / m;
            sum2 += (N - K) / m;
            sum3 += K / m;
            m *= Q[i].first;
        }
        A.push_back(sum - sum2 - sum3);
    }
    sort(A.begin(), A.end());
    cout << A[0] << endl;
}