Did you read the support article that I posted above? Your iPhone number is associated with your Apple ID, so this should be doable.... Unless your iPhone is associated with a different Apple ID. Then this will not work.
From the support article... You may have to sign out on the phone as well.
If your phone number is not listed on an iPod touch or iPad, follow these steps:
- Update to the latest version of iOS.
- Verify that you're using the same Apple ID that you are using on your iPhone.
On your iPad or iPod touch, sign out of your Apple ID in the following locations:
- Settings > Messages > Send & Receive. Tap your Apple ID, then tap Sign Out.
- Settings > FaceTime. Tap your Apple ID, then tap Sign Out.
- Sign in to your Apple ID with FaceTime and iMessage.
If your phone number is still not listed, follow these steps:
Sign out of your Apple ID on all iOS devices, including your iPhone, in the following locations:
- Settings > Messages > Send & Receive. Tap your Apple ID, then tap Sign Out.
- Settings > FaceTime. Tap your Apple ID, then tap Sign Out.
- Sign in to your Apple ID on your iPhone.
- When activation is complete, your Apple ID and all verified email addresses should be visible in Settings > Messages > Receive At and also in Settings > FaceTime.
- Now sign in to your Apple ID on your other iOS devices.