#include <bits/stdc++.h>

#ifdef DEBUG
#include <Mylib/Debug/debug.cpp>
#else
#define dump(...) ((void)0)
#endif

template <typename T, typename U>
bool chmin(T &a, const U &b){
  return (a > b ? a = b, true : false);
}

template <typename T, typename U>
bool chmax(T &a, const U &b){
  return (a < b ? a = b, true : false);
}

template <typename T, size_t N, typename U>
void fill_array(T (&a)[N], const U &v){
  std::fill((U*)a, (U*)(a + N), v);
}

template <typename T, size_t N, size_t I = N>
auto make_vector(const std::array<int, N> &a, T value = T()){
  static_assert(I >= 1);
  static_assert(N >= 1);
  if constexpr (I == 1){
    return std::vector<T>(a[N - I], value);
  }else{
    return std::vector(a[N - I], make_vector<T, N, I - 1>(a, value));
  }
}

template <typename T>
std::ostream& operator<<(std::ostream &s, const std::vector<T> &a){
  for(auto it = a.begin(); it != a.end(); ++it){
    if(it != a.begin()) s << " ";
    s << *it;
  }
  return s;
}

template <typename T>
std::istream& operator>>(std::istream &s, std::vector<T> &a){
  for(auto &x : a) s >> x;
  return s;
}

std::string YesNo(bool value){return value ? "Yes" : "No";}
std::string YESNO(bool value){return value ? "YES" : "NO";}
std::string yesno(bool value){return value ? "yes" : "no";}

template <typename T>
void putl(const T &value){
  std::cout << value << "\n";
}

template <typename Head, typename ... Tail>
void putl(const Head head, const Tail &... tail){
  std::cout << head << " ";
  putl(tail ...);
}

namespace haar_lib {
  std::vector<int64_t> enumerate_divisors(int64_t n){
    std::vector<int64_t> temp, ret;

    {
      int64_t i;
      for(i = 1LL; i * i < n; ++i){
        if(n % i == 0){
          temp.push_back(n / i);
          ret.push_back(i);
        }
      }
      if(i * i == n) ret.push_back(i);
    }

    std::reverse(temp.begin(), temp.end());
    ret.insert(ret.end(), temp.begin(), temp.end());

    return ret;
  }
}


namespace haar_lib {}

namespace solver {
  using namespace haar_lib;

  constexpr int m1000000007 = 1000000007;
  constexpr int m998244353 = 998244353;

  void init(){
    std::cin.tie(0);
    std::ios::sync_with_stdio(false);
    std::cout << std::fixed << std::setprecision(12);
    std::cerr << std::fixed << std::setprecision(12);
    std::cin.exceptions(std::ios_base::failbit);
  }

  void solve(){
    int64_t N; std::cin >> N;

    int64_t ans = N + 1;

    for(int64_t p = 2; p * p <= N; ++p){
      std::set<int64_t> s;

      int64_t t = N;

      while(t > 0){
        s.insert(t % p);
        t /= p;
      }

      if(s.size() == 1){
        chmin(ans, p);
      }
    }

    for(auto d : enumerate_divisors(N)){
      auto a = N / d - 1;
      if(d < a){
        chmin(ans, a);
      }
    }

    std::cout << ans << "\n";
  }
}

int main(){
  solver::init();
  while(true){
    try{
      solver::solve();
      std::cout << std::flush;
      std::cerr << std::flush;
    }catch(const std::istream::failure &e){
      break;
    }catch(...){
      break;
    }
  }
  return 0;
}