#include <bits/stdc++.h>
#define rep(i, a, n) for(int i = a; i < n; i++)
#define int long long
using namespace std;
typedef pair<int, int> P;
const int mod = 1000000007;
const int INF = 1e18;

struct UF{
    vector<int> par, sz;
    UF(){}
    UF(int n):par(n), sz(n, 1){
        iota(par.begin(), par.end(), 0);
    }
    int find(int x){
        if(x == par[x]) return x;
        return par[x] = find(par[x]);
    }
    void unite(int x, int y){
        x = find(x); y = find(y);
        if(x == y) return;
        if(sz[x] < sz[y]) swap(x, y);
        sz[x] += sz[y];
        par[y] = x;
    }
    bool same(int x, int y){
        return find(x) == find(y);
    }
};

signed main(){
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    int n, p;
    cin >> n >> p;
    UF uf(n + 1);
    for(int i = 2; i <= n; i++){
        if(uf.find(i) != i) continue;
        for(int j = 2 * j; j <= n; j += i){
            uf.unite(i, j);
        }
    }
    cout << uf.sz[uf.find(p)] << endl;
}