It is a happy number.
It is a semiprime because it is the product of two primes.
It is a Duffinian number.
It is an unprimeable number.
Almost surely, 221442023402355 is an apocalyptic number.
21442023402355 is an equidigital number, since it uses as much as digits as its factorization.
21442023402355 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 4288404680476.
Adding to 21442023402355 its reverse (55320432024412), we get a palindrome (76762455426767).
The spelling of 21442023402355 in words is "twenty-one trillion, four hundred forty-two billion, twenty-three million, four hundred two thousand, three hundred fifty-five".