Mukesh Ambani, Premji, Shanghvi among world's richest billionaires

India's richest business mogul Mukesh Ambani of Reliance Industries, Indian IT czar Azim Premji of Wipro and drug maker Dilip Shanghvi of Sun Pharma rank among world's top 50 wealthiest billionaires.

According to Wealth-X and Business Insider's list, released on Thursday, Ambani figures at 27th, Premji at 43rd and Shangvi at 44th among the 50 richest billionaires on the planet.

"Ambani, 58, is the richest person in India with a personal fortune (net worth) of $24.8 billion. He owns a 27-storey mansion in Mumbai that cost $1 billion to build," the report said.

The $62-billion Reliance Industries is the country's largest industrial conglomerate with interests in petrochemicals, oil and gas, textiles, natural resources, retail and telecom.

"Ambani took over as chairman of Reliance when his father (Dhirubai Ambani) died in 2002," the report said.

Premji, 70, with $16.5 billion net worth, is known for his generosity.

"In 1966, 21-year-old Azim Premji dropped out of Stanford in the wake of his father's death to take the helm of the latter's company Western India Vegetable Products (Wipro)," it noted.

Under Premji's leadership, the company diversified into toiletries and bath products and, eventually, IT, and grew exponentially.

The $7.6 billion Wipro is the country's third largest IT firm.

"Premji signed the Giving Pledge, committing to donate at least half of his wealth to charity, and in 2015 was named 'the most generous Indian' on the Hurun India Philanthropy list for the third year in a row," the report cited.

With $16.4 billion net worth, Shanghvi, 60, is a self-made industrialist, who became one of the richest Indians in 2015 for a while when his company's (Sun Pharmaceuticals Industries) blue chip stock surged on bourses.

"Graduating from University of Calcutta in 1982, Shanghvi joined his father's wholesale generic-drug business and saw an opportunity to make Lithosun, a drug that treated manic-depressive disorders," it noted.

Founded in 1983 with $1,000 investment from his father, Sun Pharma generated $100,000 in sales in its first year of business and went public a decade later in 1994. By acquiring the Michigan-based Caraco Pharmaceuticals Laboratories in 1997, the $4.5-billion Sun entered the global generic-drug market.

Stepping down in 2012 as chairman, Shanghvi serves as managing director.

Microsoft founder and renowned philanthropist Bill Gates ranked top with $87.4 billion net worth, followed by fashion retail mogul Amancio Ortega Gaona, Berkshire Hathway chief executive Warren Buffet, Amazon founder Jeff Bezos and Koch Industries brothers David Koch and Charles Koch in the top 6.

"The elite club of billionaires has a combined fortune of $1.45 trillion. The US is home to 29 billionaires, followed by China though way behind with four billionaires and India third with three billionaires among the top 50," the report added.

Of the 50 richest billionaires, 46 are males and four women, who inherited their wealth. Twelve of them are from the technology sector.

Facebook co-founder Mark Zuckerberg, ranked 8th, is the youngest billionaire with $42.8 billion net worth and 93-year-old L'Oreal Liliane Bettercourt is the oldest billionaire, ranked 17th with $29 billion net worth.