    | m == 0        = convert6 n
    | k == 0        = convert3 m ++ " million"
    | otherwise     = convert3 m ++ " million" ++ link k ++ convert6 k
    where (m, k)    = (n `div` 1000000, n `mod` 1000000)

-- Billions - 000,000,000,000's
convert12 :: Int -> String