main = getLine >>= print . solve . read . head . words

solve :: Int -> Int
solve n = n `div` f [2..n]
	where
	mb = sqrt $ fromIntegral n
	f [] = n
	f (x : xs)
		| mod n x == 0 = x
		| fromIntegral x < mb = f [y | y <- xs, mod y x /= 0]
		| otherwise = foldl (\acc y -> if acc == n && mod n y == 0 then y else acc) n xs