#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using ll = long long;
#define int ll
#define rng(i, a, b) for (int i = int(a); i < int(b); i++)
#define rep(i, b) rng(i, 0, b)
#define ALL(a) (a).begin(), (a).end()
template <class t, class u> void chmax(t& a, u b) {
    if (a < b) a = b;
}
template <class t, class u> void chmin(t& a, u b) {
    if (b < a) a = b;
}
template <class t> using vc = vector<t>;
template <class t> using vvc = vc<vc<t>>;
using pi = pair<int, int>;
using vi = vc<int>;
using uint = unsigned;
using ull = unsigned long long;
int popcount(signed t) { return __builtin_popcount(t); }
int popcount(ll t) { return __builtin_popcountll(t); }
bool ispow2(int i) { return i && (i & -i) == i; }
ll mask(int i) { return (ll(1) << i) - 1; }
int lcm(int a, int b) { return a / __gcd(a, b) * b; }
vector<pair<long long, long long>> prime_factorize(long long N) {
    // 12=({2,2},{3,1})
    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;  // 指数
        while (N % a == 0) {
            ++ex;
            N /= a;
        }
        res.push_back({a, ex});
    }
    if (N != 1) res.push_back({N, 1});
    return res;
}
int ans = 1LL << 60;

int legendre(int n, int k, pi p_pair) {
    const auto [p, num] = p_pair;
    int r = n - k;
    int cnt = 0;
    while (n) {
        n /= p;
        cnt += n;
    }
    while (k) {
        k /= p;
        cnt -= k;
    }
    while (r) {
        r /= p;
        cnt -= r;
    }
    return cnt / num;
}

signed main() {
    cin.tie(0);
    ios::sync_with_stdio(0);
    cout << fixed << setprecision(20);
    int n, k, m;
    cin >> n >> k >> m;
    auto ps = prime_factorize(m);
    for (auto p : ps) {
        chmin(ans, legendre(n, k, p));
    }
    cout << ans << endl;
}