Working with Japanese students, I have picked up a few Japanese phrases. One of the first things I taught myself was to count to ten in Japanese. I think it’s quite easy and once you have mastered this, the numbers from 11-99 are quite easy too.
While looking for ‘phonics’ songs on YouTube, I found this song. It has the same melody as ‘The Phonics Song’ in English, but is in Japanese and teaches numbers.
https://youtu.be/zqNotzty3kE