<?php

function numToWordsRec($number) {
    $words = array(
        0 => 'zero', 1 => 'one', 2 => 'two',
        3 => 'three', 4 => 'four', 5 => 'five',
        6 => 'six', 7 => 'seven', 8 => 'eight',
        9 => 'nine', 10 => 'ten', 11 => 'eleven',
        12 => 'twelve', 13 => 'thirteen', 
        14 => 'fourteen', 15 => 'fifteen',
        16 => 'sixteen', 17 => 'seventeen', 18 => 'eighteen',
        19 => 'nineteen', 20 => 'twenty', 30 => 'thirty',
        40 => 'forty', 50 => 'fifty', 60 => 'sixty',
        70 => 'seventy', 80 => 'eighty',
        90 => 'ninety'
    );

    if ($number < 20) {
        return $words[$number];
    }

    if ($number < 100) {
        return $words[10 * floor($number / 10)] .
               ' ' . $words[$number % 10];
    }

    if ($number < 1000) {
        return $words[floor($number / 100)] . ' hundred ' 
               . numToWordsRec($number % 100);
    }

    if ($number < 1000000) {
        return numToWordsRec(floor($number / 1000)) .
               ' thousand ' . numToWordsRec($number % 1000);
    }

    return numToWordsRec(floor($number / 1000000)) .
           ' million ' . numToWordsRec($number % 1000000);
}

// Example usage:
$number = 1234567;
echo "Number $number in words: "
     . numToWordsRec($number);

?>