If you liked American Tower's (AMT 1.09%) dominant position in wireless communication real estate before, you're going to love the company even more now.

On Friday, American Tower announced it has reached an agreement with Virginia-based NII Holdings (NASDAQ: NIHD) to acquire up to 2,790 towers in Brazil, and 1,666 towers in Mexico, for $413 million and $398 million, respectively -- based on today's foreign currency exchange rates, anyway.

In addition, American Tower stated it will also invest around $50 million in start-up capital expenditures associated with the two new portfolios.

This is bigger than you think
To put the significance of this news into perspective, note that this deal alone will cost half a billion dollars more than the $311.2 million that American Tower spent in the entire first half of 2013 to acquire 36 domestic towers and 1,017 international towers.

For those of you keeping track, this increases American Tower's already-enormous portfolio by around 8%, pushing it to over 60,000 communications sites worldwide.

If you're worried about how much they're spending, the company should have no problem financing the purchase. To be sure, at the midpoint of this year, American tower boasted roughly $2.6 billion in liquidity, including $448.4 million in cash and equivalents, plus the ability to borrow around $2.2 billion under two revolving credit facilities.

The folks at NII Holdings, for their part, have already agreed to lease back the towers from American Tower for a minimum of 12 years through their Nextel Brazil and Nextel Mexico subsidiaries. Why? According to NII CEO Steve Shindler in his own company's press release on the agreement, they're happy to have additional liquidity to enable them to continue investing in Nextel's next-gen network deployments in the two countries.

So what does American Tower get out of it? According to their own press release, they expect the towers to collectively generate around $149 million in annual run rate revenue, and roughly $55 million in annual gross margin.

Better yet, American Tower also expects the acquisition to be immediately accretive to adjusted funds from operations when the deal closes sometime in the fourth quarter of 2013.

What's an investor to do?
Even though shares of American Tower are trading near 52-week-lows on the heels of both so-so earnings results, which fell just short of expectations, as well as a startlingly bearish report last month from noted short-selling research firm Muddy Waters, I'm still not convinced American Tower will fall from grace anytime soon.

And I'm certainly not alone. Just last week, fellow Fool Sean Williams astutely pointed out American Tower's rare status as a profitable wireless tower provider, combined with its strategic decision to become a real estate investment trust in early 2012 -- meaning it's now legally required to distribute at least 90% of its earnings to shareholders as dividends. This makes it a truly compelling long-term investment option for patient shareholders who buy at today's levels.