If you've spent any amount of time hunting for stocks to buy in 2021, Pfizer (NYSE:PFE) and its recently authorized coronavirus vaccine probably caught your attention.

Pfizer and its partner BioNTech (NASDAQ:BNTX) rapidly developed a new vaccine to prevent COVID-19. This is an enormous achievement expected to generate more than $10 billion in top-line sales for the collaboration partners this year, and then sharply taper off in 2022. That's nothing to sneeze at, but it's important to realize Pfizer already expects more than $40 billion in total revenue this year.

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Over the past 12 months, Pfizer's profitable operation generated a whopping $10.3 billion in free cash flow, and 2021 was already shaping up to be a great year before the Food and Drug Administration (FDA) authorized its COVID-19 vaccine. Sales of Vyndaqel, a rare-disease treatment Pfizer launched in the U.S. in 2019, more than doubled year over year to reach an annualized $1.4 billion during the third quarter.

Late last year, Pfizer spun off UpJohn, its post-market-exclusivity segment, which merged with Mylan to form Viatris. The sale to Mylan netted Pfizer $12 billion in net proceeds that can be used to make dividend payments and invest in tomorrow's potential new sources of revenue.

Pfizer has raised its dividend every year since 2009, and investors who have held their shares over the past decade have seen their payouts double in size. At recent prices, the stock offers a 4.2% yield that you get to keep no matter what happens to Pfizer or the economy at large.