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:
... Balanchine, choreographer (+ 1983)
January 26 - Ancel Keys, scientist
February 1 - S. J. Perelman[?], humorist, author
February 4 - MacKinlay Kantor[?], historian ...