How many people can have access to admin password?

Answer:
I am sorry but there is no a specific number for this. Anyway, generally the admin password is only for those people that need to perform changes over a system, or over a server. A normal user that only use an information system to read email and surf through internet, does not need an admin password, but the system administrator obviously needs the admin password. Keep in mind that is a best practice that each employee has an unique user ID.

It is also a best practice to develop a password policy where you can define rules about passwords, so this template can be useful for you (you can see a free version clicking on “Free demo” tab ) “Password Policy” : https://advisera.com/27001academy/documentation/Password-Policy/

And our online course can be also interesting for you “ISO 27001:2013 Foundations Course” : https://advisera.com/training/iso-27001-foundations-course/