'That interesting enough' OR 'That interestingly enough'

[Izya]

Hi!

Dear moderators explain please.
What is correct and Why?

'That interesting enough' or "That interestingly enough"

I don't now the answer

Izya

[Torsten]

Hi Izya,

It's always good to have some context. You can say: That's interesting enough to be discussed or
You must be doing something that's interesting enough for someone to write a book about.

or

Interestingly enough, I that's the title of a new book written by...
_________________
Test Of English for International Communication
TOEIC Preparation & TOEIC Vocabulary

[Guest]

Thank you Torsten,
Izya