I wrote a small Android app for myself that has helped in my reading comprehension of numbers, in my case French numbers. Recently I put it up on the Google Play store so anyone can use it, and it's free of charge.
It's basically a number drill, something like flash cards, but with user-configurable speed, font and number format. The object is to say or think the number before the next one is shown. You can start with, say, two digit numbers every 5 seconds in a clear font, or make it difficult with phone numbers in a handwriting font.
The app will run in either English or French, depending on which language is set on your Android device. L'application fonctionne en français ou en anglais, selon les paramètres de votre appareil.
Here's the Google Play Store link: Numerus app