#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#include <atcoder/math>
using namespace atcoder;
#include <boost/multiprecision/cpp_int.hpp>
typedef boost::multiprecision::cpp_int bint;
int main(){
  bint N;
  cin >> N;

  auto euler_phi = [](bint n) {
    bint ret = n;
    for(bint i = 2; i * i <= n; i++) {
      if(n % i == 0) {
        ret -= ret / i;
        while(n % i == 0) n /= i;
      }
    }
    if(n > 1) ret -= ret / n;
    return ret;
  };

  bint e = euler_phi(N);
  vector<bint> todo;
  for (int i = 1; i * i <= e; i++) {
    if(e % i == 0){
      todo.push_back(i);
      if(e != i * i){
        todo.push_back(e / i);
      }
    }
  }
  ranges::sort(todo);
  for(bint v : todo){
    if(pow_mod(10, (ll)v, (ll)N) == 1){
      cout << v << '\n';
      break;
    }
  }
  return 0;
}
/*
  File : ~/yukicoder/528/B.cpp
  Date : 2025/02/21
  Time : 21:36:29
*/