let is_palindrome str = 
  let n = String.length str in
  List.fold_left (&&) true @@
  List.init (n/2) @@ fun i -> str.[i] = str.[n-1-i]

let () =
  let s = read_line () in
  let n = String.length s in
  Printf.printf "%s\n" @@
  if
    is_palindrome s &&
    is_palindrome (String.sub s 0 ((n-1)/2)) &&
    is_palindrome (String.sub s ((n+1)/2) ((n-1)/2))
  then "Yes"
  else "No"