22021200021221 has 4 divisors (see below), whose sum is σ = 22021225781100. Its totient is φ = 22021174261344.

The previous prime is 22021200021137. The next prime is 22021200021239. The reversal of 22021200021221 is 12212000212022.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 5639437562500 + 16381762458721 = 2374750^2 + 4047439^2 .

It is a cyclic number.

It is not a de Polignac number, because 22021200021221 - 2¹⁸ = 22021199759077 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 22021200021221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22021200021421) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11552006 + ... + 13322583.

It is an arithmetic number, because the mean of its divisors is an integer number (5505306445275).

Almost surely, 2^{22021200021221} is an apocalyptic number.

It is an amenable number.

22021200021221 is a deficient number, since it is larger than the sum of its proper divisors (25759879).

22021200021221 is an equidigital number, since it uses as much as digits as its factorization.

22021200021221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25759878.

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 22021200021221 its reverse (12212000212022), we get a palindrome (34233200233243).

The spelling of 22021200021221 in words is "twenty-two trillion, twenty-one billion, two hundred million, twenty-one thousand, two hundred twenty-one".