3.56m hit by Hammer of Light?

I’m sorry but why is it that a class can hit 3.56million against a fully geared target?

The reason I ask is because the most I hit on a full geared up Destro Warlock is probably 3.2m against an undergeared character with a damage buff to hit that king of number.

I heard from other people that it sometimes hits for 6m?

Clearly broken?