The world's 5 richest of the rich

No. 1: Carlos Slim Helú / $ 53.5 trillion / telecom

Mexico Telecom Tycoon, who pounced on the privatization of the national telecommunications company in the 1990s, is the world's richest person for the first time after he came in third place last year. Net worth up $ 18.5 billion a year. Recently received regulatory approval to merge its fixed-line resources to America Mobile (AMX), Latin America's largest mobile-phone company. His construction conglomerate, Impulsora del Desarrollo y el Empleo, build roads and energy infrastructure.

Son of Lebanese immigrants also owns stakes in financial Inbursa (GPFOY), Bronco Drilling (BNRC), Independent News & Media, Saks (SKS) and The New York Times Co. (NYT). Newspaper company shares jumped in early March to talk Slim can buy a controlling stake, he denied the rumors. Donating $ 65 million to fund a research in genomic medicine with American billionaire philanthropist Eli Broad.

No. 2: Bill Gates / $ 53 trillion / Microsoft

Software Visionary is now the world's second richest man. Net worth is still up $ 13 billion in a year that Microsoft (MSFT) shares rose 50% in 12 months, the value of the investment vehicle Cascade Investments also swelled.

More than 60% of assets held outside of Microsoft; investments include Four Seasons Hotels, Grupo Televisa (TV) and Auto Nation (AN). Stepped down from day to day duties at Microsoft in 2008 to focus on philanthropy. Bill & Melinda Gates Foundation dedicated to fighting hunger, improving education in U.S. high schools and developing vaccines against malaria, tuberculosis and AIDS.

No. 3: Warren Buffett / $ 47 trillion / investments

America's premier investor up to $ 10 billion in the last 12 months on rolling Berkshire Hathaway (BRK.A) shares, says the U.S. has survived "economic Pearl Harbor", but warns recovery will be slow. Wisely invested $ 5 billion in Goldman Sachs (GS) and $ 3 billion in General Electric (GE) during the 2008 market collapse. Recently bought railroad giant Burlington Northern Santa Fe for $ 26 billion.

"We have put a lot of money to work during the chaos the past two years," said Buffett. "When it rains gold range for a bucket, not a thimble."

Berkshire Hathaway book value was up 19.8%, to $ 21.8 billion in 2009. Son of Nebraska stockbroker met value investor Benjamin Graham while he was studying economics at Columbia University. Took over textile firm Berkshire Hathaway in 1965, used the company as a vehicle to invest in insurance (GEICO), food (Dairy Queen), utilities (MidAmerican Energy) and recently, green tech (electric-car maker BYD).

No. 4: Mukesh Ambani / $ 29 trillion / petrochemical, oil and gas

Global ambitions: His Reliance Industries, is already India's most valuable company, recently bid $ 2 billion for 65% of the shares in the troubled Canadian oil sands outfit Value Creations. Company's $ 14.5 billion offer to buy bankrupt petrochemical maker LyondellBasell was rejected. Since September, the company has sold Treasury shares worth $ 2 billion will be used for acquisitions.

Late father, Dhirubhai founded Reliance and built it into a massive conglomerate. After the elder Ambani's death, Mukesh and his brother Anil, ran the family business together for a short time. But the brothers feuded over control, the mother finally brokered a split of assets, Mukesh get energy, oil and gas and petrochemicals businesses. Still at odds with Anil over gas supply agreement. Are cricket team Mumbai Indians.

No. 5: Lakshmi Mittal / $ 28.7 trillion / steel

London's richest resident supervision ArcelorMittal (MT), the world's largest steel maker. Net profit fell 75% in 2009. Mittal took 12% salary cut in the middle of recession, but a better outlook pressured stock up third in the last year.

Wants to expand in the country of India, wants to build steel mills in Jharkhad and Orissa but has not received official approval. Started in the family steel business in India in 1970, branched out on his own in 1994. Initially acquired steel mills on the cheap in Eastern Europe. Earned 1.1 billion U.S. dollars to sell its stake in a Kazakh refinery in December.

Board member of Goldman Sachs (GS) and the European Aeronautic Defense and Space (EADSF). Increased stake in struggling British football team Queens Park Rangers in February. Funding 400-foot sculpture to be built in London's Olympic Park in time for the 2012 Olympics. Are 12-bedroom mansion in London's posh Kensington neighborhood. Daughter-in-law Megha recently acquired insolvent German fashion house Escada.