Should SEO numbers be written in text or numbers?

Question

Search Engine Optimization

For SEO in the url of the article, write numbers in text or numbers?
For example:
"3 days after .." - 3 dnya after or
"three days after .." - tri dnya after
does it matter at all?
And the same percentage in the title should be indicated with a sign or text?
"3% of Russians.."
"three percent of Russians..
Thank you.

Answer 1

Doesn't matter at all. Search engines understand both numbers and letters, write as you like.

Answer 2

For SEO, you need to write as your users write in the search