User blog comment:Primussupremus/big number./@comment-5029411-20170226171244/@comment-28606698-20170226180955

The number is considered "salad number" if it was generated using two or more different notations.

Your base number $$k=891$$ (number of nines as I calculated using MS Word)

first notation generate number $$n=\sum_{i=0}^k (9\times 10^i)$$

and then you apply this n to second notation - arrow notation.

Your big number=$$6 \uparrow^n 6$$