#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using V = vector<ll>;
using VV = vector<V>;
using VVV = vector<VV>;
using VVVV = vector<VVV>;
using VVVVV = vector<VVVV>;
using VVVVVV = vector<VVVVV>;
using VS = vector<string>;
using VB = vector<bool>;
using VVB = vector<VB>;
using P = pair<ll,ll>;
using M = map<ll,ll>;
using Q = queue<ll>;
using PQ = priority_queue<ll>;
using PQG = priority_queue<ll,V,greater<ll>>;
using S = set<ll>;
using VP = vector<P>;
const ll MOD = 1000000007;
const ll mod = 998244353;
const ll INF = 1LL << 60;
#define rep(i,n) for(ll i = 0; i < n; i++)
#define rep2(i,s,n) for(ll i = s; i < n; i++)
#define per(i,n) for(ll i = n-1; i >= 0; i--)
#define per2(i,s,n) for(ll i = n-1; i >= s; i--)
#define all(x) (x).begin(),(x).end()
#define rall(x) (x).rbegin(),(x).rend()
#define fi first
#define se second
#define pb push_back
#define pf push_front
#define ppb pop_back
#define ppf pop_front
#define eb emplace_back
#define lb lower_bound
#define ub upper_bound
template<class T>bool chmin(T&a, const T&b){if(a>b){a=b;return true;}return false;}
template<class T>bool chmax(T&a, const T&b){if(a<b){a=b;return true;}return false;}
template<class T>void Vin(vector<T>&a){rep(i,(ll)a.size())cin>>a[i];}
template<class T>void VVin(vector<vector<T>>&a){rep(i,(ll)a.size())Vin(a[i]);}
template<class T>void Vout(const vector<T>&a){rep(i,(int)a.size()-1)cout<<a[i]<<" ";cout<<a.back()<<'\n';}
template<class T>void Voutl(const vector<T>&a){rep(i,(int)a.size())cout<<a[i]<<'\n';}
ll power(ll a,ll b,const ll&M){a%=M;ll res=1;while(b>0){if(b&1)res=res*a%M;a=a*a%M;b>>=1;}return res;}
const ll H[4] = {0,1,0,-1}, W[4] = {1,0,-1,0};

struct Sieve {
    long long n;
    vector<long long> f, primes;
    Sieve(long long n): n(n), f(n+1) {
        f[0] = f[1] = -1;
        for(long long i = 2; i <= n; i++) {
            if(f[i]) continue;
            primes.push_back(i);
            f[i] = i;
            for(long long j = i*i; j <= n; j += i) if(!f[j]) f[j] = i;
        }
    }
    bool isPrime(long long x) {
        return f[x] == x;
    }
    vector<long long> factorList(long long x) {
        if(!x) return {};
        vector<long long> res;
        while(x != 1) {
            res.push_back(f[x]);
            x /= f[x];
        }
        return res;
    }
    vector<pair<long long,long long>> factor(long long x) {
        vector<long long> fl = factorList(x);
        if(fl.size() == 0) return {};
        vector<pair<long long,long long>> res = {{fl[0],0}};
        for(long long p : fl) {
            if(p == res.back().fi) res.back().se++;
            else res.emplace_back(p,1);
        }
        return res;
    }
    vector<pair<long long,long long>> bigfactor(long long x) {
        if(!x) return {};
        vector<pair<long long,long long>> res;
        for(long long p : primes) {
            long long y = 0;
            while(x%p == 0) x /= p, y++;
            if(y) res.emplace_back(p,y);
            if(x == 1) break;
        }
        if(x != 1) res.emplace_back(x,1);
        return res;
    }
};

int main() {
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    int n;
    cin >> n;
    int ans = 1;
    Sieve s(n + 1);
    ll sz = s.primes.size();
    ll y = 1;
    S st;
    per(i, sz) {
        if(y * s.primes[i] > n) {
            cout << "? " << y << endl;
            ll z;
            cin >> z;
            VP p = s.bigfactor(z);
            for(auto q : p) {
                st.insert(q.fi);
                ans *= q.fi;
            }
            y = 1;
        }
        y *= s.primes[i];
        if(i == 0) {
            cout << "? " << y << endl;
            ll z;
            cin >> z;
            VP p = s.bigfactor(z);
            for(auto q : p) {
                st.insert(q.fi);
                ans *= q.fi;
            }
            y = 1;
        }
    }
    for(ll x : st) {
        if(ans * x > n) break;
        ll z = 1;
        while(z <= n) z *= x;
        z /= x;
        cout << "? " << z << endl;
        ll t;
        cin >> t;
        ans *= t / x;
    }
    cout << "! " << ans << endl;
}