Saving large Word document

I am trying to save a large Word document (about 3000 pages) and it creates exception, that document is too large.
Is there a limit? For now, I broke the file into three 1000 pages docs and it works fine, but how to know what is the limit? Microsoft says that there is no size limit for their Word files.
Please reply.
Thank you.

Thanks for your inquiry. No there is no limit of document’s size. The limit is memory (because the document needs to be held wholly in memory) and document complexity. It also depends what you are going to do with it.
Anyway it is better to use few small documents instead one huge document.
Best regards.