Maximum HRs vary widely between individuals. I'm 57, I still see numbers in the 180s occasionally. As Greg says, it's more useful to work out your threshold and base your training on that.

And having a low resting HR does not mean you will necessarily have a low maximum. My own resting HR is currently 48. So my max is about 380% of the resting rate. But that will have zero relevance to you because of the individual variations.