The former late-night host discussed the upcoming season of The Celebrity Apprentice on Access Hollywood Live on Wednesday (January 5) and revealed that he's struck up a close relationship with Aiken.
"[Clay's] the sweetest guy, a good friend too," Hall said of the singer. "He's charming, he's bright and he's one of my best friends... Something about me and Clay bonded."
Hall added that he enjoyed meeting Star Trek actor George Takei, who is also competing on The Celebrity Apprentice.
"He's the greatest guy to work with. There are times when everything goes to hell and he says [imitating Takei], 'Ohhhhh, my!'," the star recalled.
This season of Celebrity Apprentice features the show's largest cast ever with 18 contestants, which Hall admitted might work against him in the boardroom.
"They almost didn't want me there [at all], much less, let me win," the comic teased.
Adam Carolla, Debbie Gibson and Lisa Lampanelli are among the 18 stars appearing on The Celebrity Apprentice, which returns on Sunday, February 12 at 9pm ET/PT on NBC.
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