What should the regular expression look like?

Question

Regular Expressions

Good afternoon, how to make a regular expression for checking &1234577934 (starts with & and then a number)
I tried this const reg = /^$|\&?\d$/ - does not work ((

Answer 1

And you insert your regular into https://regex101.com/ and there it will be written on the side how it works.
You have a lot of weird and unnecessary checks.
Enough&\d+

Answer 2

probably it is necessary to have word boundaries, otherwise it will not highlight the word but its part,
for example: abc &123
\b&\d+\b tried, but something does not work?
Threat
to breathe like this \B&\d+\b
https://regex101.com/r/3yDtDi/1