I'm not sure what it is, but I know there is a minimum. I know that if you have an Amazon capsule, you will need at least 50 words as a description to keep it from being overpromotional.
But why try to write the minimum? If you want your hubs to be successful, you should explain whatever the topic is thoroughly, so that your readers will want to come back again to read it, and refer other readers to it.
I agree with ptosis. Make separate paragraphs, and separate headings so it is easy to read.