Apple had a lot of big numbers to share during their Q1 2011 earnings today. And while the biggest unsurprisingly belonged to the iPhone, the iPad numbers are also very, very impressive. How impressive? The iPad business is already a bigger business than Apple’s portable computer business. That includes MacBooks, MacBook Pros, and MacBook Airs. And it’s within spitting distance of surpassing Apple’s entire Mac business in terms of revenue.

Last quarter, Apple sold 7.33 million iPads. Broken down, they made just over $4.6 billion off of the product for the quarter. That puts it ahead of the $3.69 billion the MacBook business made for Apple during the same time frame.

The iPad actually nearly started outselling Macs right out of the gates in terms of actual units (which did happen last quarter). But the higher price points of Macs ensured that they maintained an edge in revenues. But the iPad was able to surge past the MacBooks in that category this past quarter thanks to a huge spike in sales, while the MacBooks sales rose less dramatically.

But perhaps even more impressive is that the iPad is already closing in on Apple’s total Mac business. The portable plus desktop (iMac, Mac mini, Mac Pro, and Xserver) sales totaled $5.43 billion in revenue last quarter. So the iPad just needs another $800 or so million to surpass it. That will happen at some point this year. Perhaps even next quarter depending on when the iPad 2 is unveiled.

In total, Apple has now sold 14.8 million iPads since the device’s launch last April.

More: Apple’s Cook On iPad/Mac Relationship: “If This Is Cannibalization, It Feels Pretty Good.”