object Main extends App {
  val sc = new java.util.Scanner(System.in)
  val S = sc.next()
  val f = (s: String) => s == s.reverse
  val i = (S.length - 1) / 2
  println(if (f(S) && f(S.take(i)) && f(S.reverse.take(i))) "Yes" else "No")
}
