Want to know the most important ingredient to success as an investor? Time. The longer your time horizon, the more likely you'll make money. That's true for small retail investors as well as famous investors.

Small investors can sometimes get good ideas by looking at the portfolios of famous investors. Multibillionaire George Soros, for example, owns more than 50 stocks in his Soros Fund Management hedge fund. Several of them could make you plenty of money by buying and holding for the long term. Here are the three Soros stocks that are most likely to turn $200,000 into $1 million over the next 20 years, in my view. 

What it would take

Before we get to those stocks, let's first look at what it would take to turn $200,000 into $1 million over the next two decades. Most importantly, the companies need to simply stay in business throughout the period. 

That might seem like an easy task. However, one of the stocks in Soros' portfolio at the end of the second quarter no longer exists as a standalone entity. Astellas Pharma acquired Iveric Bio in July.

Mathematically, the key to delivering a fivefold return over 20 years is to grow by an average of around 8.4% annually. Again, that doesn't sound like too much of a stretch. But some of the stocks that Soros owns have such lofty growth expectations baked into their share prices already, achieving that level of return over the long run might not be a walk in the park.

I think there are several stocks in Soros' portfolio that could be five-baggers or better. However, picking the ones that are most likely to do so requires evaluating their financial strength, competitive advantages, market opportunities, and track records. With all of those criteria in mind, three Soros stocks especially stand out to me.

Multiple common denominators

So what are those three stocks? Listing them in alphabetical order: Alphabet (GOOG -1.33%) (GOOGL -1.33%)Amazon (AMZN -0.89%), and Microsoft (MSFT -0.68%). These stocks share multiple common denominators.

For one thing, they've all far exceeded a fivefold return over the past 20 years. Amazon has been the biggest winner with its shares skyrocketing roughly 6,600%. Google parent Alphabet has given investors a 5,100% return. Microsoft lags far behind yet has still soared more than 11 times over.

All three companies continue to generate impressive growth. Again, Amazon leads the way with a year-to-date gain of over 50%. Alphabet isn't too far behind with its shares up nearly 50% so far in 2023. Microsoft trails these two but is nonetheless up more than 30%.

More importantly, Alphabet, Amazon, and Microsoft have highly resilient businesses. The companies have moats -- competitive advantages that give them staying power. Alphabet dominates search. Amazon is the 800-pound gorilla in e-commerce and ranks as the market leader in cloud services. Microsoft rules the operating system and productivity software markets.

Each of these stocks should also be able to deliver strong growth going forward. In particular, artificial intelligence (AI) seems likely to serve as a major tailwind for all three. The rapid adoption of AI will almost certainly drive more organizations to the cloud. That's great news for Alphabet's Google Cloud unit, Amazon Web Services, and Microsoft's Azure cloud platform. 

Slam-dunk five-baggers?

There are no guarantees with any stocks, even giants such as Alphabet, Amazon, and Microsoft. It's even possible that the tremendous size of these three companies could work against them in delivering fivefold returns over the next 20 years.

However, I fully expect that AI and cloud services will be much bigger markets two decades from now. And I would be shocked if Alphabet, Amazon, and Microsoft weren't leaders in both markets. No, they aren't slam-dunk five-baggers. Of all the stocks in Soros' portfolio right now, though, I'd be most comfortable putting my money on these current winners.