As others are pointing out, this is actually a popular site not just for russian content. Owing to the jurisdiction, it's actually a popular place for hosting various ripped/pirated PDFs.
If you actually click through Google's result pages, you will find that there are actually only about 87 results. Even if you "repeat the search with the omitted results included" Google returns only about 226 results. Google's estimated result count is routinely off by so much as to make it virtually useless.
I found that going to the last page showed a more realistic number for results. This would only be shown on that "last page" of results though. However, it does seem strange that there are only 447 results for a google search of "apple"[0] down from a whopping 4,070,000,000 results shown before that page. And that is with show omitted results. Seems like max result limiting for the 0.1% of users that want to look past page 10 of search results
It is actually plausible that there could be billions of pages with apple on the internet.
The 447 results you paged through are just the most relevant docs for your particular query ("apple" + country) and Google doesn't bother retrieving any further. Your use case of finding all the pages with the term "apple" is simply too rare and too expensive to support and they don't optimize for it.
If you try different query variants apple + something with different locales (&hl=) you'd get very different top NNN results.
Google like all other web search engines never scan their whole index when searching, it's way too expensive. All sorts of tricks are used to aggressively prune matching results at every opportunity during retrieval until maybe a few hundred best scoring docs are left and that's what you're paging through.
But yeah, estimated result count is still a big lie either way
