#include<bits/stdc++.h>
using namespace std;

int main(){
  ios::sync_with_stdio(false);
  cin.tie(nullptr);
  int N;
  cin>>N;
  vector<int>prime(N+1,1);
  vector<int>ask;
  for(int i=2;i<=N;i++){
    if(prime[i]==0)continue;
    int t=i;
    while(t*i<=N)t*=i;
    ask.push_back(t);
    for(int j=i*i;j<=N;j+=i){
      prime[j]=0;
    }
  }
  random_device sd;
  mt19937 rd(sd());
  shuffle(ask.begin(),ask.end(),rd);
  int ans=1;
  for(int i=0,t;i<min(600,(int)ask.size());i++){
    cout<<"? "<<ask[i]<<endl;
    cin>>t;
    ans*=t;
  }
  cout<<"! "<<ans<<'\n';
}