main :: IO ()
main = do
  n <- readLn :: IO Integer
  m <- readLn :: IO Integer

  putStrLn $ if any (\x -> x/=2&&x/=5) $ factor m primes
    then "-1"
    else [head $ dropWhile (=='0') $ reverse $ n`divL`m]

primes :: [Integer]
primes = 2:sieve [3] [3,5..]
  where
    sieve (x:xs) ys = let
        (ps, qs) = span (<x^2) ys
      in ps ++ sieve (xs++ps) (filter ((/=0).(`mod`x)) qs)

factor :: Integer -> [Integer] -> [Integer]
factor n pss@(p:ps)
  | p*p>n        = [n]
  | n`mod`p == 0 = p:factor (n`div`p) pss
  | otherwise    = factor n ps

divL :: Integer -> Integer -> String
divL n m
  | n == 0 = ""
  | otherwise = show (n`div`m)++divL (n`mod`m*10) m