There are 498 pages in the Hardcover version and 544 pages in the Paperback.
"A Prayer for Owen Meany" by John Irving has approximately 637 pages in its paperback edition.
The Twilight of Briareus has 255 pages.
Planet of Twilight has 416 pages.
The Twilight of Atheism has 306 pages.
A Caress of Twilight has 441 pages.
Twilight of the Idols has 208 pages.
Twilight Eyes has 464 pages.
Crossroads of Twilight has 704 pages.
Tara of the Twilight has 288 pages.
The Servants of Twilight has 432 pages.
Jedi Twilight has 368 pages.
there are 4 ; but if your counting the book about Bree then 5 in total based on the twilight world.