Yes, it's just a number referenced in one of a few databases.

> The 15-digit pet microchip is the international standard (see ISO 11784:1996 and ISO 11785:1996)

https://www.aaha.org/for-veterinary-professionals/microchip-...

https://en.wikipedia.org/wiki/ISO_11784_and_ISO_11785

>the international standard

Except the United States, because of course.

ISO is 134 kHz, US has both 125 and 128 kHz.