The direction of the numbers is in the eye of the beholder. In English, 123 is one hundred and twenty three. In Arabic, it would be three and twenty and one hundred. Therefore, for Arabic readers, the numbers are read right to left, just as the letters and they are as much in the right order as latin numbers are in the right order for you.
Just to confuse you, in German the number would be one hundred three and twenty.

Peter