import Data.Char (digitToInt)

digits :: String -> [Int]
digits n = let m = map digitToInt n in filter (flip elem m) [0 .. 9]

solve :: String -> Integer
solve s = gcd n $ fromIntegral (foldr gcd 0 [abs (x - y) * 9 | x <- ds, y <- ds])
    where
        n = read s :: Integer
        ds = digits s

main :: IO ()
main = getLine >>= print . solve