#include <iostream>
using namespace std;
typedef long long ll;
ll gcd(ll n,ll m){
    if(n%m==0) return m;
    else return gcd(m,n%m);
}
ll N,P;
int main(){
    cin >> N >> P;
    int ans = 0;
    for(ll i=2;i<=N;i++){
        ll g = gcd(i,P);
        if(g!=1) ans++;
        else if(i/g*P<=N) ans++;
    }
    cout << ans << endl;
}