Numberblocks Wiki
Numberblocks Wiki

Eighty-One, or 81, is an Numberblock made of 81 blocks.


Eighty-One has 80 pink blocks and 1 red block, his eyes, mouth and his limbs are all pale blue.

Episode Appearances



In We're Going on a Square Hunt, 9 referred to him as '9×9'. He made an appearance in The Big One as a compound until his figured out form debuted in Square on the Moon.


  • Eighty-One is the first numberblock in the 80s to be figured out.
  • Eighty-One sneezes like Nine because he is 9x9.
  • Eighty-One doesn't usually show his legs. His figured-out form first appeared as a picture in Thirty-Six; his full body was visible in Square on the Moon, although the legs showed only in a close-up shot.
  • Eighty-One is the 4th fourth power to be figured out, the first, second and third being One, Sixteen, and Ten Thousand, respectively.
  • He is also the 4th square to be male.
  • Eighty-One, like Sixteen (character), is almost a super rectangle with 5 factors.
  • Some viewers think that his 'one' is like his nose.