It is a happy number.
It is an unprimeable number.
Almost surely, 221213363130024 is an apocalyptic number.
It is an amenable number.
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
21213363130024 is a wasteful number, since it uses less digits than its factorization.
21213363130024 is an evil number, because the sum of its binary digits is even.
Adding to 21213363130024 its reverse (42003136331212), we get a palindrome (63216499461236).
The spelling of 21213363130024 in words is "twenty-one trillion, two hundred thirteen billion, three hundred sixty-three million, one hundred thirty thousand, twenty-four".