https://annas-blog.org/worldcat-scrape.html
The blog post is not of interest, but at the bottom there is an interesting line that caught my attention:
"Special call for LLM companies and groups: we recently launched a special program on Anna’s Archive to help out teams building LLMs with high-speed access to our collections." ... That is - 21,616,998 books, 97,847,479 papers, 2,451,040 comics, 508,998 magazines