310-597-3781. That number showed up on the caller ID of a cell phone on last week's 24. The phone number belongs to a crew member who's been bombarded with calls since the episode aired. Now, the phone's been hanging out on set, and cast and crew members have been answering and chatting up fans.
The line was busy when I tried, so I think I'll give it another go in the morning.
This is similar to the 916-CALL-TURK number that's sometimes answered by cast and crew from Scrubs. I can never get anything but Turk's voicemail, though. Dr. Kelso's the outgoing message these days.