How to get Hex form ARGB

package druva {
	import flash.display.Sprite;

	public class ColorUtils extends Sprite {
		public function ColorUtils() {
		}

		public static function ARGBtoHex(a:Number, r:Number, g:Number, b:Number) {
		return (a << 24 | r << 16 | g << 8 | b);
	}

	}
}