If you're a 40-year-old investor, you're probably not planning on retiring for another 20 years or more. While that may be bit of a downer for those looking forward to the freedom that retirement can bring, the positive is that it gives you more than two decades to grow your investments as you prepare for that big day.

This ultra-long-term investment horizon can be a major advantage for you over other investors -- if you use it wisely. One of the best ways to do so is to seek out businesses with growth opportunities that span across many years and that are fueled by major secular trends. Even better is if these companies possess strong economic moats, which can help them make the most of these opportunities.

Fortunately, we can invest in one such business today. Read on to learn more about it.

A compass pointing toward the word growth

Image source: Getty Images.

China's 1.4 billion population and rapidly growing $11 trillion economy  can provide investors with fertile ground from which to grow a fortune. One company, in particular, is positioned to profit from this massive opportunity perhaps more than any other: Alibaba Group (NYSE:BABA).

The $475 billion Alibaba Group is one of the most powerful companies in the world. Yet among U.S. investors, the Chinese internet behemoth remains relatively unknown. Therein lies our opportunity.

A wide moat

With a mission "to make it easy to business anywhere,"  Alibaba dominates Chinese commerce, with an estimated 11% share of China's $5 trillion retail market, based on its gross merchandise volume (the amount of goods and services purchased on its platform). Alibaba has even grander ambitions, however. Chairman and co-founder Jack Ma says the 18-year-old giant is "still a baby," as Ma envisions a future in which Alibaba becomes an economy unto itself that serves 2 billion consumers around the world. It's certainly a bold goal, but not one that's entirely unreasonable considering Alibaba already has 500 million customers in China alone.

Alibaba Group's empire spans across a collection of leading wholesale and retail online marketplaces, as well as cloud computing, digital media, and entertainment businesses, among others. Notably, Alibaba's Taobao Marketplace is the No. 1 e-commerce app in China as measured by mobile monthly active users, and its Tmall.com is the No. 1 business-to-consumer site in China by market share.

Massive growth opportunities

China's burgeoning middle class is ushering in a powerful wave of growth for its already massive economy. Rising income levels -- per capita income in China has increased at an 11% annual pace since 2010 -- and changing attitudes toward consumption are fueling a surge in consumer spending. Many of these purchases are taking place via online channels.

These trends have been a boon for Alibaba. In fiscal 2017, revenue surged 45% year over year, to $19.5 billion, in Alibaba's core commerce segment and 271%, to $2.1 billion, in its digital media and entertainment division. All told, Alibaba's revenue soared 56% to $23 billion, and adjusted earnings per share leapt 40% to $3.41. This is exceptional growth for any company -- and especially for one the size of Alibaba.

Management projects Alibaba's revenue to continue to rise at a torrid pace, to the tune of 49% to 53%  in fiscal 2018. Looking out even further, Alibaba believes it can achieve $1 trillion in GMV by 2020, up from $547 billion in fiscal 2017.

An attractive price 

For such a competitively advantaged and rapidly growing business, Alibaba's stock is surprisingly inexpensive. Shares are currently trading at about 27 times analysts' estimates for fiscal 2019. That's quite a bargain for a business that's expected to deliver earnings growth of more than 30% in the year ahead.

All told, with its strong economic moat and long runways for growth, Alibaba is the type of stock that can serve 40-year-old investors well. And those who buy today should be well rewarded in the years -- and potentially, decades -- ahead.

Joe Tenebruso has no position in any of the stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. The Motley Fool has a disclosure policy.