• George Clooney's phone number is saved on Julia Roberts' cell under the contact name "Batman."
• Clooney famously played the Dark Knight in 1997's "Batman and Robin."
• Roberts revealed her code name for Clooney during an interview for their upcoming film "Ticket to Paradise."

Julia Roberts has a special nickname for her close friend George Clooney on her phone: Batman.

During an interview for the pair's upcoming rom-com, "Ticket to Paradise," Good Day Chicago's Jake Hamilton asked Roberts how they're saved in each other's phone

"George is in my phone under code name 'Batman's cell,'" she replied.

The reveal appeared to surprise Clooney, who responded to his friend by asking, "Batman's cell? Oh, that's funny."

"Now I have to change it," Roberts said.

"Yeah, everybody knows," Clooney agreed.

Without missing a beat, Hamilton joked that Clooney's updated contact name could be "Bat nipples," referencing the controversial nipples that were added to Clooney's Batsuit.

In 2013, Clooney told Deadline he keeps a photo of himself as the Dark Knight displayed on his office wall "as a cautionary reminder of what can happen when you make movies solely for commercial reasons."

The Joel Schumacher-directed movie was a critical and commercial box-office failure.

But how is Roberts saved in Clooney's phone?

Clooney joked that Roberts is in his phone under "Pretty Woman," referencing the actor's popular 1990 film costarring Richard Gere.

Roberts didn't buy that for a second.

"No it's not," Roberts said, calling him out.

Clooney admitted she was right.

"It's not Julia Roberts because my phone gets picked up," Clooney said, sharing he doesn't usually use full names for contact info. "I think it's just J.R. or something like that."

You can watch the pair's five-minute interview with Hamilton below. They start discussing how they're saved in each other's phones at the 3:13 mark.

Watch:

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