Nineteen billion dollars is no small sum. That's the amount (including the value of common shares and restricted stock units) that Facebook (NASDAQ:FB) has agreed to pay for WhatsApp, a multiplatform messaging service that bypasses SMS and uses the Internet for messages. As Fool contributor Daniel Sparks explains in the video below, $19 billion is enough to buy some formidable companies.

While it's surprising that Facebook paid that much for a 55-employee messaging service that is only five years old, Daniel suggests investors look past the surface. Not only does WhatsApp have a highly engaged massive base of 450 million monthly active users, but this base is growing fast -- faster than Facebook was at that stage, actually.

Nevertheless, it's useful to see what kind of value $19 billion could buy by looking at comparable publicly traded companies. Check out the video below to see what else Facebook could have purchased with that massive sum.