open System

let factorize n =
  let split p n =
      let mutable n = n
      let mutable k = 0L
      while n % p = 0L do
          k <- k + 1L
          n <- n / p
      (n, k)
  let f (p, n) =
    if p <= n then
        let (m, k) = split p n
        let elem = if k > 0L then Some (p, k) else None
        Some (elem, (p + 1L, m))
    else None

  Seq.unfold f (2L, n) |> Seq.choose id |> Map.ofSeq

let solve n =
  factorize n
  |> Map.toSeq
  |> Seq.choose (fun (k, v) -> if v % 2L <> 0L then Some k else None)
  |> Seq.fold (*) 1L

[<EntryPoint>]
let main _ =
  let x = Console.ReadLine() |> int64
  printfn "%d" (solve x)

  //exit code
  0