Tom Hanks Credits Likability to His 'Goofy Voice and Big Butt'

Tom Hanks is one of the most beloved actors in Hollywood, but, as Steven Spielberg revealed to ET, there is one thing fans will be surprised to know about him.

Hanks and Spielberg sat down with ET's Cameron Mathison to talk about their upcoming film Bridge of Spies, but the subject quickly turned personal when the Oscar winners started disclosing details about one another.

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The 59-year-old actor doesn't deny his worldwide likability, but jokingly credits his popularity to his "goofy voice and the big butt."

Spielberg gave us one more reason to love Hanks when he revealed that he writes personal letters to people on a "typewriter that is at least 60 years old." That's just old school cool!

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As for what would surprise fans about the 68-year-old acclaimed director, Hanks says Spielberg does not drink any coffee. "No stimulants," he revealed. "No legal, addictive stimulants are in his world."

Bridge of Spies is the fourth film that Hanks and Spielberg have worked on together, following behind Saving Private Ryan, Catch Me If You Can and The Terminal.

"The best part of working with him more than once is you don't have the pain of that first 'getting to know you' day," Hanks admitted.

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The thriller, which hits theaters Oct. 16, is about an American lawyer (Hanks) who is recruited by the CIA during the Cold War to help rescue a pilot detained in the Soviet Union.

Here's a closer look at Hanks and Spielberg's bromance: