You'll be stopped by game performance long before that XD. I've reached the 600s and ultimately gave up due to lagg.
I am curious about 5k tho. I think enemy growth is exponential, so unless you found a way to scale exponentially, they'll catch up by then. My linear 8 million damage and 500k HP per floor growth should've started being outmatched by floor 1000 or so. And sure, those two values are getting multiplied again for total damage. But still not exponential.