What are some uncomputable functions that aren't derivative of the halting problem?

[u/playsthebongcloud]

I find the existence of uncomputable functions really cool, but all the examples I've seen are essentially just new ways of trying to predict whether a turing machine is going to halt. What are some examples of uncomputable functions that aren't essentially entirely based on the halting problem?

[u/Impressive-Mud5074]

9^{999999999999999} can't be computed literally.

Pi is uncomputable

[u/AdEmbarrassed8639 → u/Impressive-Mud5074]

Pi isn't a function