Asia has more billionaires than any other continent, followed by North America and Europe, according to a survey by a China-based wealth magazine released on Thursday.
There were 1,453 people around the world with a personal wealth of $1 billion or more as of January, said the Hurun Report, a luxury magazine publisher that compiled the list.
Asia had 608 billionaires, North America 440 and Europe 324, it said in a statement.
Among individual countries, the United States and China dominated with 408 and 317 citizens respectively on the list, followed by Russia, Germany and India.
Mexican telecoms czar Carlos Slim, 73, was ranked as the "Richest Man on the Planet" with a personal fortune of $66 billion. Slim also topped the Forbes magazine annual global rich list last year.
US investor Warren Buffett and Amancio Ortega of Spain, founder of fashion brand Zara, were second and third in the Hurun Report list with net worth of $58 billion and $55 billion respectively.
It estimated the total wealth of the world's dollar billionaires at $5.5 trillion, roughly the size of the Japanese economy last year.
"This past year has seen a rebound in the wealth of the private sector," it said, adding the net assets of the 10 richest people on the list rose 22 percent over the year, or $250 million a day.
Real estate, telecommunications, media and technology and retail were the most common sources of wealth, it added.
Rupert Hoogewerf, chairman and chief researcher of the Hurun Report, said the true number of billionaires in the world could be three times higher as some super-rich hid their worth.
"Some people deliberately make their wealth a secret because... they gained it through illegal ways," he told reporters at a press conference. "Some others simply prefer to keep a low profile."
Hoogewerf, an accountant by training, previously compiled the Forbes rich list.