Which piece of information can never be changed after creating a new user profile?

The piece of information that can never be changed after creating a new user profile is the Social Security Number. This is a key identifier that is often used for verification and legal purposes. By design, it is meant to remain constant to ensure the integrity of identity verification processes and to prevent fraudulent alterations that could affect the security and authenticity of a user's identity.

Changing the Social Security Number could lead to confusion and complications in tracking records, thus it is treated as a permanent piece of information within most systems. In contrast, usernames and email addresses can often be updated as users change their preferences or switch email services. Phone numbers can also be modified as a user's contact information may change over time. However, the significance and unchangeability of the Social Security Number make it distinct in this context.