If all of your stat points were put into health then that puts your level at around 619.
At level 81with every skill at 100, you would need to reset and re-level 147 times just to reach level 252, at which point you could buy literally every single perk point, effectively making the need to legendary again, useless. Unless you wanted the extra challenge. But it wouldn't really be a challenge sitting at 2620 health. It'd actually be horrifyingly boring with no enemies to match your level (even on legendary difficulty). You'd both just be standing there taking piss poor damage from attacks.
So presuming you powered through the torturous boredom and grind of fighting over and over and over again you are faced with another challenge. Levelling up.
omg that would be hell. To go from 81 to 252 takes a skill reaching 100 147 times. It is implied that your character is around level 619.
The algorithm for levveling is:
XP required to level up your character = (Current level + 3) * 25
So yours would be (from level 252): (252 +3) * 25
So the xp needed to go from just 252 to 253 would be 6375xp.
But going towards your end of the spectrum:
level 599 moving to level 600
(599 +3) * 25
= 15050xp
now do that 19 more times adding the extra xp as needed.
It's late and I'm bored so sorry that this is off topic and a bit dickish but I have to ask
Pics or didn't happen.