#include<bits/stdc++.h>
#define rep(i,n) for(int i=0; i< (n); i++)
using namespace std;
typedef long long ll;
typedef pair<int,int> P;
const int mod = 998244353;
const int inf = (1<<30);
const ll INF = (1ull<<62);

ll f(ll n,ll k){//k ha sosuu
    ll ans = 0;
    while(n > 0){
        ans += n/k;
        n /= k;
    }
    return ans;
}


int main(){
    ll n,k,m; cin>>n>>k>>m;
    ll t = n-k;
    ll ans = inf;
    for(ll i = 2; i*i <= m; i++){
        if(m%i != 0) continue;
        int c = 0;
        while(m%i == 0){
            m/=i;
            c++;
        }
        ans = min(ans,(f(n,i) - f(k,i) - f(t,i))/c);
    }
    if(m>1) ans = min(ans,(f(n,m) - f(k,m) - f(t,m)));
    cout<<ans<<endl;
}