For things that are completely software, it does not surprise me that millions per employee in earnings is realized - that's just what happens when you operate at that scale. And that's accounting for all of the overhead in personnel that scale entails.
Even then, they can still be insanely profitable per engineer.
I like "MAGNAM" if you include Microsoft.
Some of these measures make it look like Google's zero-customer-support approach is the 'efficient' way to run a business but for a lot of companies it'd be a false economy.