Latin script in Unicode – Wikipedia
As of version 9.0 of the Unicode Standard, 1,350 characters in the following blocks are classified as belonging to the Latin script
Let’s remove the uppercase letters; and that leaves us with your answer. From eyeballing:
26+30+128+104+14*8+12+12+67+26 = 517
That leaves 833.
If I’m wrong, I’m not wrong by much.
EDIT: Derek Zech’s answer to How many letters does Unicode currently include in the Latin script, no matter the language, but ignoring upper vs. lower case differences? leaves out more letters than I do, is more thorough, and he sounds more correct. Go upvote him: Vote #1 Derek Zech.