Bill Gates has been declared the richest man in the world for the 16th time by Forbes magazine's annual ranking of global billionaires.
The Microsoft co-founder's net worth has risen to $US79.2 billion, from $US76 billion last year.
There are a record 1826 billionaires on its list this year up from 1645 in 2014, the magazine said.
In second place on this year's list is Mexico telecommunications mogul Carlos Slim Helu, with a net worth of $US77.1 billion. He had topped the list in 2013.
Next is investor Warren Buffett, who moved up one slot with a net worth of $US72.7 billion. His fortune grew $US14.5 billion from a year earlier, more than anyone's else, despite his having donated $US2.8 billion to several charities last July.
Amancio Ortega, the Spanish founder of Inditex, which includes clothing retailer Zara, was fourth at $US64.5 billion, while Oracle Corp Chairman Larry Ellison was fifth at $US54.3 billion.
The youngest billionaires were Evan Spiegel, 24, and Bobby Murphy, 25, who co-founded mobile messaging app Snapchat, and are each worth $US1.5 billion.
Zuckerberg moves up, Jordan joins list
Facebook's Mark Zuckerberg joined the top 20 and basketball star Michael Jordan made the list for the first time.
The 30-year-old rose to 16th place from 21st last year, as his net worth grew to $US34.8 billion.
Meanwhile, Michael Jordan ranked 1,741st with a $US1 billion net worth. The 52-year-old is majority owner of the Charlotte Hornets basketball team, but is better known for his Hall of Fame playing days with the Chicago Bulls and endorsement contract with Nike Inc, which makes Air Jordan shoes.
Of the record 197 women, the highest-ranked was Wal-Mart heiress Christy Walton, who was eighth at $41.7 billion.
France's Liliane Bettencourt, who got much of her wealth from cosmetics company L'Oreal, was 10th at $40.1 billion.
The United States had the most billionaires, with 536, followed by China at 213, Germany at 103 and India at 90. Russia, which has struggled with currency and oil market turmoil, saw its collection of billionaires fall to 88 from 111, Forbes said.
It's the 29th year for Forbes billionaires' list.
-AFP/ RTR / BBC