Depends how you define "novel" I suppose.
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Just full prose novels published as such: 19
Including eBooks: Add another 2 (Recovery, Ylesia) or even 3 (Boba Fett: A Practical Man)
Including graphic novels: Add another 3 (Invasion Volume 1, Volume 2, Volume 3) or even 4 (Chewbacca)
I agree that magazine/serialized short stories don't count (The Apprentice, Emissary to the Void), but surely the eBooks might.