Unique incremental ID identifier

Unique incremental ID identifier

Hello. I'm building an automated flow for a shipping company that follows: 
  1. A customer registers from our website
  2. It becomes a lead in the system.
  3. They receive a new account email that must contains:
    1. {Name of the company} + prefix XXXX (unique ID identifier) 
    2. The ID must be visible on the new customer profile from the admin panel.
How can I mirror this?
Thanks.