Now the 77-year-old media mogul apparently wants to be president, too. He is preparing to file paperwork in Alabama to qualify for that state's presidential primary. He has one big supporter already--fellow billionaire businessman Leon Cooperman, an outspoken critic of leading Democratic candidate Elizabeth Warren.

Bloomberg is wealthy enough to fund his own campaign. Forbes estimates his current net worth at $52.4 billion-an amount that dwarfs not only the value of President Donald Trump's real estate empire, but also the fortunes of fellow media moguls Rupert Murdoch, Ted Turner, and Sumner Redstone combined.

Just how did Bloomberg, a Boston native and son of an accountant and a secretary, amass his fortune?

Wall Street as we know it today wouldn't exist without his innovations. After earning his MBA from Harvard Business School in 1966, he got a job counting securities by hand in the "The Cage" at the former New York investment bank known as Salomon Brothers.

Bloomberg became a Wall Street star at the firm, whose leaders later convinced him to manage the company's fledgling computer systems unit in 1979.

Eventually Bloomberg worked his way up to general partner before being let go in 1981, when Salomon merged with commodities trading firm Phibro Corporation. He received a $10 million severance.

He used that money to begin building his financial media empire, co-founding Innovative Market Systems with Charles Zegar, Thomas Secunda, and Duncan MacMillan the same year.

"I didn't sit around wondering what was happening at the old firm," Bloomberg wrote in his 2001 autobiography "Bloomberg by Bloomberg". "I didn't go back and visit. I never look over my shoulder. Once finished: Gone. Life continues!"

The then-39-year-old used the financial know-how and information technology expertise he developed at Salomon to create the Bloomberg terminal in 1982, a software system with a specialized keyboard used by financial professionals to trade stocks electronically and access live market data.

The apparatus revolutionized an analog Wall Street and became a ubiquitous tool used in investment banking, competing with Thomson Reuters Eikon, FactSet, and S&P Capital IQ.

Innovative Market Systems was renamed Bloomberg L.P. in 1986. In 1990, the company created its own news service before launching Bloomberg.com in 1993.

Not content with business success, Bloomberg ran for mayor of New York City in 2001, succeeding Rudolph Giuliani in the aftermath of 9/11. Bloomberg's time as mayor was riddled with controversial policies such as stop-and-frisk policing, the rise of charter schools, and pressuring the city council to temporarily change the rules on term limits so he could run for a third term.

But New York City's overall quality of life improved under Bloomberg's tenure. Crime rates dropped. Graduation rates at city schools rose. So did city revenues and Bloomberg's own net worth.

Bloomberg L.P.'s terminal user base has more than doubled, to 325,000 subscribers currently from 160,000 in 2001, according to the company.

With a price point of $24,000 per subscriber for its terminals, the privately-held company's annual revenue eclipsed $10 billion in 2018, according to an analyst estimate.

In March, Forbes ranked Bloomberg as the ninth richest person in the world and the wealthiest media mogul on the planet.