#include <bits/stdc++.h>
using namespace std;
 
int main() {
  string s, t;
  cin >> s;
  t = s;
  reverse(t.begin(), t.end());
  int n = s.size();
  if(s == t and s.substr(0, (n - 1) / 2) == s.substr((n + 3) / 2 - 1, n - 1)){
      cout << "Yes";
  }
  else{
      cout << "No";
  }
}