function int2wordsDE( num, out ) {
	var word;
	var rem;
	var i;
	if ( num === 0 ) {
		// Case: We have reached the end of the number and the number is zero.
		return out || 'null';
	}
	if ( num < 0 ) {
		out += 'minus ';
		num *= -1;
	}
	if ( num < 20 ) {
		rem = 0;
		if ( num === 1 && out.length === 0 ) {
			word = 'ein';
		} else {
			word = ONES[ num ];
		}
	}
	else if ( num < 100 ) {
		rem = num % 10;
		word = TENS[ floor( num / 10 ) ];
		if ( rem ) {
			word = ( ( rem === 1 ) ? 'ein' : ONES[ rem ] ) + 'und' + word;
			rem = 0;
		}
	}
	else if ( num < 1e3 ) {
		rem = num % 100;
		word = int2wordsDE( floor( num / 100 ), '' ) + 'hundert';
	}
	else if ( num < 1e6 ) {
		rem = num % 1e3;
		word = int2wordsDE( floor( num / 1e3 ), '' ) + 'tausend';
	}
	else {
		for ( i = 5; i < UNITS.length; i++ ) {
			if ( num < UNITS[ i ].VAL ) {
				rem = num % UNITS[ i-1 ].VAL;
				if ( floor( num / UNITS[ i-1 ].VAL ) === 1 ) {
					word = 'eine ' + UNITS[ i-1 ].DE;
				} else {
					word = int2wordsDE( floor( num / UNITS[ i-1 ].VAL ), '' ) + ' ' + pluralize( UNITS[ i-1 ].DE );
				}
				if ( rem ) {
					word += ' ';
				}
				break;
			}
		}
	}
	out += word;
	return int2wordsDE( rem, out );
}
Converts a number to a word representation in German.

@private
@param {number} num - number to convert
@param {string} out - output string
@returns {string} word representation

@example
var words = int2wordsDE( 1243, '' );
// returns 'eintausendzweihundertdreiundvierzig'

@example
var words = int2wordsDE( 387, '' );
// returns 'dreihundertsiebenundachtzig'

@example
var words = int2wordsDE( 100, '' );
// returns 'einhundert'

@example
var words = int2wordsDE( 1421, '' );
// returns 'eintausendvierhunderteinundzwanzig'

@example
var words = int2wordsDE( 100381, '' );
// returns 'einhunderttausenddreihunderteinundachtzig'

@example
var words = int2wordsDE( -13, '' );
// returns 'minus dreizehn'