Jeff Bezos has got to be in a good mood this holiday season.

A month ago, Amazon (AMZN - Get Report) was enjoying a lucrative Black Friday weekend. But the good times for Amazon's CEO didn't end then. During the third week of December, the world's largest online retailer added 3 million new Prime members on its way to a very merry Christmas.

Prime is the bread and butter of Amazon's business, with members gaining access to benefits like free shipping and video streaming in exchange for a $99 annual fee.

Amazon gets a lot out of its Prime members, who spend an average of $1,000 or more at the Web site compared to non-Prime members, according to ITG analyst Steve Weinstein. Research firm Millward Brown estimates that Prime members are almost five times more likely to make a purchase in the same shopping session compared to non-Prime members.

This all translates to a nightmare for other retailers who are struggling to grab the attention of these loyal Prime members.

While Amazon is traditionally tight-lipped about sharing exact numbers on Prime membership, in 2013, the company said that it had "tens of millions" of Prime members worldwide, and at the end of 2014, the company said global Prime subscriptions were up 53% and North America subscriptions were up 50%.

The Consumer Intelligence Research Partners estimates that Amazon has reached 44 million U.S. Prime members, and according to analysts at Cowen, U.S. Prime subscriptions reached 40 million in October. RBC Capital Markets analyst Mark Mahaney thinks the U.S. number could already be close to 50 million.

Amazon also shared that Prime members doubled their viewing hours of Prime Video compared to last year's holiday season, an important growth metric in Amazon's growing content business. Plus, Christmas Eve was the biggest and busiest day ever for Prime Now deliveries, according to the company.

Additionally, sales of Amazon devices were more than twice last year's holiday sales, with the Fire TV and Fire TV stick hitting the No. 1 and No. 3 spot respectively for top-selling products across all of the items available on Amazon.com over the past month.

That's a lot of holiday cheer from one company.