There are many different numbering schemes for assigning numbers to entities. These generally require an agreed set of rules, or a central coordinator.
Numbering schemes include:
The E.164 numbering plan for telephone numbers, including:
... are
confined to several passages, viz., the merit of good
works and transubstantiation (iv. 2), purgatory
(iv. 9), and the worship of saints (i. 13, ii. 9, iii. 6,
59). ...