That's assuming that they're revenue is spread out evenly over every day and every minute. Which is not the case. Think Christmas, deals, weekends, time of the day, etc...
It also assumes that everybody who goes to buy something from Amazon while its down end up buying somewhere else as opposed to simply waiting until later that day
That's less than I expected! Back at the height of their popularity, I remember hearing that AOL could lose a lot of money every second their servers weren't showing ads.
61.1 Billion dollars (yearly revenue) / 31556926 seconds = 1936.18 dollars/second