Mobile Number Total

In general, if the telephone is primarily for personal or family use, the telephone number is best when it matches or is compatible with the person's destiny number, which is the number 6 for the information you provided.

When the telephone is primarily for business/career, or primarily for social activities, then generally the number that matches or is compatible with the life path number is preferred. That would be the number 5 for the birth date you provided.

The chart at the Compatibility of Number Energy page can be consulted for compatibility.

I'm uncertain how a mobile would be for "own" or for "birthdate". But perhaps the telephone number compatibility tool can assist.