Lachhman Das Mittal, 92, is India's oldest billionaire after the death of Keshub Mahindra, who passed away on April 12 aged 99. He's the Founder and Chairman of Sonalika Group. Born in 1931, he started his career as an insurance agent. Mittal later retired and became an entrepreneur at 65. His net worth is $2.5 billion, according to Forbes.