#include <bits/stdc++.h>
//#include<boost/multiprecision/cpp_int.hpp>
//#include<boost/multiprecision/cpp_dec_float.hpp>
//#include <atcoder/all>
#define rep(i, a) for (int i = (int)0; i < (int)a; ++i)
#define rrep(i, a) for (int i = (int)a - 1; i >= 0; --i)
#define REP(i, a, b) for (int i = (int)a; i < (int)b; ++i)
#define RREP(i, a, b) for (int i = (int)a - 1; i >= b; --i)
#define repl(i, a) for (ll i = (ll)0; i < (ll)a; ++i)
#define pb push_back
#define eb emplace_back
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define popcount __builtin_popcount
#define popcountll __builtin_popcountll
#define fi first
#define se second
using ll = long long;
constexpr ll mod = 1e9 + 7;
constexpr ll mod_998244353 = 998244353;
constexpr ll INF = 1LL << 60;

// #pragma GCC target("avx2")
// #pragma GCC optimize("O3")
// #pragma GCC optimize("unroll-loops")

//using lll=boost::multiprecision::cpp_int;
//using Double=boost::multiprecision::number<boost::multiprecision::cpp_dec_float<128>>;//仮数部が1024桁
template <class T>
inline bool chmin(T &a, T b)
{
	if (a > b)
	{
		a = b;
		return true;
	}
	return false;
}
template <class T>
inline bool chmax(T &a, T b)
{
	if (a < b)
	{
		a = b;
		return true;
	}
	return false;
}

template <typename T>
T mypow(T x, T n, const T &p = -1)
{ //x^nをmodで割った余り

	if (p != -1)
	{
		x =(x%p+p)%p;
	}
	T ret = 1;
	while (n > 0)
	{
		if (n & 1)
		{
			if (p != -1)
				ret = (ret * x) % p;
			else
				ret *= x;
		}
		if (p != -1)
			x = (x * x) % p;
		else
			x *= x;
		n >>= 1;
	}
	return ret;
}

using namespace std;
//using namespace atcoder;

void solve()
{	
  ll n;
  cin>>n;
  if(n==1){
    cout<<2<<"\n";
    return;
  }else if(n==2){
    cout<<3<<"\n";
    return;
  }
  ll ans=n-1;
  auto check=[n](ll i,int j)->ll{
    ll l=2,r=n;
    constexpr ll maxv=INF;
    while(r-l>1){
      ll mid=(l+r)/2;
      ll x=1;
      bool ng=false;
      rep(num,j){
        if(x<=maxv/mid)x*=mid;
        else if(num!=j-1){
          ng=true;
          break;
        }
      }
      if(ng){
        r=mid;
        continue;
      }
      if((x-1)/(mid-1)<=i&&(x-1)<=i*(mid-1))l=mid;//前半はオーバーフロー対策,後半は切り捨ての関係
      else r=mid;
    }
    ll x=1;
    rep(num,j){
      if(x<=maxv/l)x*=l;
      else if(num!=j-1){
        return INF;
      }
    }
    if((x-1)%(l-1))return INF;
    ll val=(x-1)/(l-1);
    if(val==i&&n/val<=l-1)return l;
    else return INF;
  };
  for(ll i=1;i*i<=n;++i){
    if(n%i==0){
      rep(j,41){
        chmin(ans,check(i,j));
      }
      if(i*i!=n){
        rep(j,41){
          chmin(ans,check(n/i,j));
        }
      }
    }
  }
  cout<<ans<<"\n";
}

int main()
{
	ios::sync_with_stdio(false);
	cin.tie(nullptr);
	cout << fixed << setprecision(50);
	solve();
	return 0;
}