quadrillion vs septendecillion

quadrillion

num
  • A thousand trillion (logic: 1,000 × 1,000^4): 1 followed by fifteen zeros, 10¹⁵. 

noun
  • Any very large number, exceeding normal description. 

septendecillion

num
  • 10¹⁰². 

  • 10⁵⁴. 

How often have the words quadrillion and septendecillion occurred in a corpus of books? (source: Google Ngram Viewer )