Dell CEO Michael Dell delivers a keynote address at the 2007 Oracle Open World conference November 14, 2007 in San Francisco, California.

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Call it the billion-dollar bromance.The growing friendship between President Donald Trump and Michael Dell has coincided with a banner year for the billionaire CEO.Dell shares are up 240% this year, while the man himself has added $83.5 billion to his net worth. He's now the world's 6th-richest person with a staggering $223 billion to his name.BI's Polly Thompson has more on how Dell's relationship with Trump has paid off big time.Business people buddying up to Trump, or any politician, isn't groundbreaking. However, Dell's approach came with low reputational risk: giving money to kids.The cornerstone of the recent bonding has been Dell and his wife, Susan, contributing $6.25 billion to Trump Accounts back in December. Since then, Trump has purchased more than $1 million in Dell stock, and the company won a $9.7 billion contract with the US Department of Defense.And then there was the public endorsement from the president, who put the spotlight on Dell in a way it hasn't enjoyed since the "Dude, you're getting a Dell" commercials of the early 2000s.