Same here (72 750) but it doesn't feel right. I'm not a native speaker and I was able to guess some of them via elimination or cognates.

I'd say I know 10 000 words tops.

You may know more words than you think, many are shared with French and other Romance languages, particularly the more esoteric ones (see what I did there?). Taking another recherché example: palimpsest - very similar in English, French, Greek.