Man, I see this debated all the time. The most common benchmark I've run into is around 70,000 to 100,000 words, but page count is such a slippery beast because of font size, margins, and trim size. If you force me to pick a number, for a typical mass-market paperback, I'd say 300 to 400 pages feels like the sweet spot that signals 'standard novel' to me.
Publishers definitely think in word count first, though. I got a rejection once that literally said 'does not meet our minimum word count for the category,' which was 80k. That's stuck with me. A 250-page book with dense prose might hit that word count, while a 400-page book with lots of dialogue and white space might not. It's why asking about pages can be misleading for writers.
For a real-world example, take something like 'The Hunger Games.' My edition is 374 pages, and it squarely fits that commercial, standard-length novel feel. Anything much under 250 pages starts to drift into novella territory in the reader's mind, even if the word count technically qualifies.