It is a semiprime because it is the product of two primes.
It is a cyclic number.
It is a Duffinian number.
Almost surely, 221021033120011 is an apocalyptic number.
21021033120011 is an equidigital number, since it uses as much as digits as its factorization.
21021033120011 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 678097842612.
Adding to 21021033120011 its reverse (11002133012012), we get a palindrome (32023166132023).
The spelling of 21021033120011 in words is "twenty-one trillion, twenty-one billion, thirty-three million, one hundred twenty thousand, eleven".