//TLE解
#include <iostream>
#include <algorithm>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
using ll = long long;
//#define endl "\n";
int main(){
  ll X;
  cin >> X;
  ll chk = X * 11;
  while(1){
    vector<ll> v;
    ll tmp = chk;
    while(tmp > 0){
      v.push_back(tmp % 10);
      tmp /= 10;
    }
    bool isOK = true;
    for(int i = 1; i < v.size(); i++){
      if(v[i] != v[v.size() - 1 - (i - 1)]){
        isOK = false;
        break;
      }
    }
    if(isOK){
      cout << chk << endl;
      return 0;
    }
    chk += X * 10;
  }
  return 0;
}