21201221022 has 16 divisors (see below), whose sum is σ = 44634149760. Its totient is φ = 6695122392.

The previous prime is 21201221021. The next prime is 21201221051. The reversal of 21201221022 is 22012210212.

It is a junction number, because it is equal to n+sod(n) for n = 21201220992 and 21201221010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21201221021) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 92987698 + ... + 92987925.

It is an arithmetic number, because the mean of its divisors is an integer number (2789634360).

Almost surely, 2^21201221022 is an apocalyptic number.

21201221022 is an abundant number, since it is smaller than the sum of its proper divisors (23432928738).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21201221022 is a wasteful number, since it uses less digits than its factorization.

21201221022 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 185975647.

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 21201221022 its reverse (22012210212), we get a palindrome (43213431234).

The spelling of 21201221022 in words is "twenty-one billion, two hundred one million, two hundred twenty-one thousand, twenty-two".