(Please read whole post since I realize my mistake partway through.

)
Truthfully I'd be perplexed if I don't even know the gender of the main character by page 180! Unless the character is disguising themselves or comes across sort of androgynously? I'd understand the other characters not being certain of such things, but how does one get through 180 pages without revealing the main character's gender? How do you refer to this character--he, she, it, they?
If it's simply a matter of referring to the MC as he or she or something when that's not REALLY what they are, then I understand, this can increase reader suspense and uncertainty. But the character has to be referred to in
some way, even if it's later shown they're not what the reader thinks they are.
Regarding their sexuality, in truth I'm MORE interested in reading about gay characters, *LOL.*

But it depends on the reader. I doubt it'd make most readers put the book down based on that alone. Whether it's publishable depends on the publisher, but gay characters don't seem to really make books unpublishable nowadays.
But I must confess I'm baffled about not revealing the main character's gender until so late in the story, unless, like I said, it's just a matter of subterfuge.
*checks original post, which is good, because--*
OH!
180 words, not pages.

Sorry about that! You know, 180 words is really a small amount in regards to a novel. That's no big deal. Sometimes the main character doesn't even show up in the first chapter! But I leave the rest of what I typed up because it's really best to give SOME idea of the MC's gender early on, even if it's misleading information (e. g., saying they're a guy when really they're a woman, and not revealing the truth until later).