It sometimes pays to check out stocks that experts really like. By experts, I'm referring to investors who have achieved tremendous success and analysts who spend most of their time researching stocks.

Bill Ackman is a good example of a wildly successful investor. He has amassed a fortune of close to $4 billion, thanks to shrewd moves with his hedge fund, Pershing Square Capital Management.

The multibillionaire investor doesn't like many stocks. And several of them aren't favored by Wall Street. There's at least one notable exception, though. Ackman owns $1.8 billion of this stock -- and 38 Wall Street analysts recommend buying it right now.

Ackman's top stock

Ackman isn't a fan of building a highly diversified portfolio. Pershing Square Capital Management owns only eight stocks, but two of the stocks in Ackman's portfolio are for one company. He owns Alphabet Class A (GOOGL 10.22%) shares and Alphabet Class C (GOOG 9.96%) shares.

With both classes of shares combined, Google parent Alphabet ranks as Ackman's top holding. Pershing Square's stake in the technology giant is currently worth just a tad over the aforementioned $1.8 billion level.

This isn't a long-held position for Ackman. He initiated a position in Alphabet in early 2023. When the hedge fund CEO first bought the stock, it was down because of a mishandling of the launch of generative artificial intelligence (AI) app Bard. Many investors thought that Alphabet was being left behind by OpenAI's ChatGPT.

Ackman, however, saw a great opportunity in the pullback. As he told CNBC in September 2023, he believes that Alphabet "will be a dominant player in AI for the very, very long term."

A lot of Alphabet bulls on Wall Street

Wall Street is largely in agreement with Ackman about Alphabet. Financial information company LSEG surveyed 43 analysts who cover the stock. Thirteen rated Alphabet as a strong buy, with another 25 recommending it as a buy.

What about the remaining five analysts? All of them recommended holding Alphabet stock, with none thinking it should be sold.

Granted, many on Wall Street aren't expecting Alphabet shares to soar this year after its explosive 58% gain in 2023. The average 12-month price target reflects a modest upside potential of around 9%.

Argus analyst Joseph Bonner's views on Alphabet are probably representative of quite a few others on Wall Street. Bonner wrote to investors recently, "Alphabet remains at minimum competitive if not a leader in the development of generative AI, perhaps the new computing paradigm." He added that Argus is "positive on Alphabet's underlying businesses and believe[s] that GOOGL shares are attractively valued."

Are Ackman and analysts right about Alphabet?

Even the so-called experts can be wrong. In this case, though, I think that both Ackman and Wall Street analysts are spot on about Alphabet.

The company is, without question, one of the leaders in AI development. I expect the launch of Gemini Ultra will provide a nice catalyst for Google Cloud.

Alphabet revealed in December 2023 that Gemini Ultra beat the current state-of-the-art AI models (in many cases, OpenAI's GPT-4) in 30 of 32 benchmarks. The new AI model also is the first to outperform human experts on the MMLU (massive multitask language understanding) test, which includes 57 subjects.

I don't think that Google Search faces an existential threat from AI, either. On the contrary, Alphabet could benefit from AI integration. A good example is Google's recent introduction of Circle to Search for Android phones, a way to search for anything with a quick gesture without switching apps.

The company and the stock could face a few bumps in the road along the way (including antitrust investigations). However, I fully expect that Alphabet will be a big winner over the long term -- just as it has been since its initial public offering (IPO) in 2004.