#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>ask1,ask2;
  for(int i=2;i<=N;i++){
    if(prime[i]==0)continue;
    int t=i;
    while(t*i<=N)t*=i;
    if(t!=i)ask1.push_back(t);
    else ask2.push_back(t);
    for(int j=i*i;j<=N;j+=i){
      prime[j]=0;
    }
  }
  long long ans=1;
  int cnt=0;
  for(int i=0,t;i<min(600,(int)ask1.size());i++,cnt++){
    cout<<"? "<<ask1[i]<<endl;
    cin>>t;
    ans*=t;
  }
  random_device sd;
  mt19937 rd(sd());
  while(ask2.size()&&ans*ask2.back()>N)ask2.pop_back();
  shuffle(ask2.begin(),ask2.end(),rd);
  for(int i=0,t;i<min(600-cnt,(int)ask2.size());i++){
    cout<<"? "<<ask2[i]<<endl;
    cin>>t;
    ans*=t;
  }
  cout<<"! "<<ans<<'\n';
}