To give some supplementary information, my Azumarill has Huge Power, but when she gets confused (she gets confused a lot) and hits herself, I notice that the damage isn't that high, around 20 HP.
Her attack stat is currently 68 at L45, but with Huge Power it's 136. I'm not sure about her IVs because she's my in-game Azumarill. Her defence is 89 and HP is 155.
I notice that with my Linoone:
L49, HP 143, Attack 92, Defence 85
and she seems to hit herself for more damage than my Azumarill, around 35+ HP.