no vs not at all

no

adv
  • not 

  • Used before different, before comparatives with more and less, and idiomatically before other comparatives. 

  • Used idiomatically before certain other adjectives. 

prep
  • not, does not, do not, etc. 

  • without 

  • like 

intj
  • vehement rejection of truthfulness 

  • disgust 

  • mild disapproval 

particle
  • Used to show disagreement, negation, denial, refusal, or prohibition. 

  • Used together with an affirmative word or phrase to show agreement. 

  • Used to show agreement with a negative question. 

det
  • Not any. 

  • Hardly any. 

  • Not (a); not properly, not really; not fully. 

  • Not any possibility or allowance of (doing something). 

noun
  • a negating expression; an answer that shows disagreement, denial, refusal, or disapproval 

  • a vote not in favor, or opposing a proposition 

not at all

adv
  • Not in the least. 

intj
  • Used similarly to you're welcome, as a conventional reply to an expression of gratitude. 

  • Don't worry about it (response to worry or an apology) 

How often have the words no and not at all occurred in a corpus of books? (source: Google Ngram Viewer )