Tesla CEO Elon Musk grew up in South Africa and worked in Canada before coming to the US.

Net worth: $20.7 billion

Source of wealth: PayPal, Tesla

Musk, 48, first moved to the United States to attend the University of Pennsylvania, Business Insider previously reported. The CEO founded a city guide service for newspapers called Zip2 and an online banking named X.com that got acquired by PayPal before taking the top job at Tesla.

Read more: Elon Musk is worth about $22 billion and has never taken a paycheck from Tesla — here's how the notorious workaholic and father of 5 makes and spends his fortune