Once Aadhaar Number is issued to the resident, it cannot be changed or modified in any way even if you update your details of Aadhaar. Even after updating your details in Aadhaar, the details will be updated against the same Aadhaar Number which you were been issued. Instead, Aadhaar is a 12 digits unique random number that is linked with the resident's demographic and biometric data. So your 12 digit Aadhaar Number will be the same for lifelong.