What is the user ID of a user that have all the privileges of a root user?

The user ID (UID) of a user that has all the privileges of a root user is 0. The root user is the superuser

account that can perform any action on the system, such as changing file ownership, binding to

network ports below 1024, or executing any command. The root user is identified by the UID 0, not

by the name “root”, which is just a convention. It is possible to have another user account with the

name “root”, but not with the same UID 0.