21022331021 has 8 divisors (see below), whose sum is σ = 21541088184. Its totient is φ = 20503860480.

The previous prime is 21022331009. The next prime is 21022331023. The reversal of 21022331021 is 12013322012.

It can be written as a sum of positive squares in 4 ways, for example, as 454755625 + 20567575396 = 21325^2 + 143414^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21022331021 - 2²⁶ = 20955222157 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21022331023) 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, 80795 + ... + 220391.

It is an arithmetic number, because the mean of its divisors is an integer number (2692636023).

Almost surely, 2^21022331021 is an apocalyptic number.

It is an amenable number.

21022331021 is a deficient number, since it is larger than the sum of its proper divisors (518757163).

21022331021 is a wasteful number, since it uses less digits than its factorization.

21022331021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 143311.

The product of its (nonzero) digits is 144, while the sum is 17.

Adding to 21022331021 its reverse (12013322012), we get a palindrome (33035653033).

Subtracting from 21022331021 its reverse (12013322012), we obtain a palindrome (9009009009).

The spelling of 21022331021 in words is "twenty-one billion, twenty-two million, three hundred thirty-one thousand, twenty-one".