#include <bits/stdc++.h>

using namespace std;

bool check(const string &s, int m) {
  int r = 0;
  for (char c: s) {
    r = 10 * r + (c - '0');
    r %= m;
  }
  return r == 0;
}

long long gcd(long long a, long long b) {
  if (b == 0)
    return a;
  return gcd(b, a%b);    
}

string solve(const string &s) {
  vector<int> v;
  for (char c: s)
    v.push_back(c - '0');
  sort(v.begin(), v.end());
  v.erase(unique(v.begin(), v.end()), v.end());

  if (v.size() == 1)
    return s;
  
  long long g = 0;
  for (int a: v)
    for (int b: v)
      g = gcd(g, 9 * abs(a - b));

  for (int x = g; x > 1; x--) {
    if (g % x == 0 && check(s, x))
      return to_string(x);
  }

  return "1";
}


int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);

  string s;
  cin >> s;

  cout << solve(s) << endl;
  
  return 0;
}