Elon Musk got $4.5 billion richer overnight, as Tesla's share price continues to surge.

Musk, who owns about 19% of the company's stock, or 34.1 million shares, saw the value of his holdings jump by $4.5 billion as the company's shares climbed more than 17% between Monday's close and midmorning trading Tuesday. Musk has added more than $17 billion to his net worth just this year — more than any other billionaire in the world. To put that into perspective, he has made $500 million a day — or $20 million an hour — since Jan. 1.

Musk still has a long way to go to topple Jeff Bezos as the world's No. 1. With more than $40 billion, Musk is still $80 billion behind Amazon's founder, according to Bloomberg Billionaires Index. But he is gaining fast. Bezos is up only $9 billion this year, while Bill Gates is up about $2 billion, according to share filings.

Yet the speed of Musk's wealth gain is almost unprecedented. Bezos famously gained $40 billion in wealth during a 12-month period in 2017 and 2018. But Bezos has earned more than a third of that in just 34 days.

Put another way, Musk has added a Marc Benioff and a Rupert Murdoch to his wealth just in 2020, both of whom have roughly $7.9 billion in net worth.

So what would Tesla stock have to hit for Musk to pass Bezos as the world's richest man?

Musk is currently ranked about 20 in the world. For him to pass Bezos' roughly $125 billion, Tesla stock would have to hit $3,665. And if Musk hit that share price — plus a profit target of $14 billion a year, as well as other financial targets — he would also get a compensation bonus of more than $50 billion from Tesla. That would put his total net worth at more than $175 billion, which would make Musk the richest man ever.