let f m n =
    let f0 i r = if n%i=0L then i else r
    let rec f1 i r = if i>2L then f1 (i-1L) (f0 i r) else r
    let f2 i = if i<>4L && n%2L=0L then i/2L else i
    match (f1 m 0L) with
    | 0L -> f2 n
    | i -> i

let g = float >> sqrt >> floor >> int64

let h n = f (g n) n

stdin.ReadLine() |> int64 |> h |> printfn "%d"