singles = " one two three four five six seven eight nine ".split
teens = "ten eleven twelve thirteen fourteen fifteen sixteen seventeen eighteen nineteen ".split
tys = "  twenty thirty forty fifty sixty seventy eighty ninety".split
ions = "thousand million billion".split

numberName = function(n)
    if n == 0 then return "zero"
    a = abs(n)
    r = ""  // (result)
    for u in ions
        h = a % 100
        if h > 0 and h < 10 then r = singles[h] + " " + r
        if h > 9 and h < 20 then r = teens[h-10] + " " + r
        if h > 19 and h < 100 then r = tys[h/10] + "-"*(h%10>0) + singles[h%10] + " " + r
        h = floor((a % 1000) / 100)
        if h then r = singles[h] + " hundred " + r
        a = floor(a / 1000)
        if a == 0 then break
        if a % 1000 > 0 then r = u + " " + r
    end for
    if n < 0 then r = "negative " + r
    return r
end function

// Test cases:
for n in [-1234, 0, 7, 42, 4325, 1000004, 214837564]
    print n + ": " + numberName(n)
end for