This is not correct for Chart of Account numbers they are limited to 7 digits included "." and blank spaces.  In most accounting systems at the ERP level, you can have account numbers such as:

5000.1000.250.1000 and more if necessary where:

5000 is COGS for example

1000 is  Profit Center

  250 is Department Code

and 1000 is Division or Company Code

5000 is a subtotal of all COGS

5100 is a subtotal within COGS

5150 is the actual account, etc.