Old Droid still shows phone number

[Character Zero]

I recently upgraded from a Droid 1 to the Thunderbolt. I want to sell the old Droid, so I did a factory reset. But when I go into setting and look at the phone info it still shows my phone number. I verified that it cannot receive or make calls, should I be concerned my number is still showing?

 

[Snow02]

If you can flash the baseband that will remove it. But it's really not a big deal.