21231110321 has 8 divisors (see below), whose sum is σ = 22396402080. Its totient is φ = 20070605088.

The previous prime is 21231110317. The next prime is 21231110353. The reversal of 21231110321 is 12301113212.

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 21231110321 - 2² = 21231110317 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 21231110321.

It is not an unprimeable number, because it can be changed into a prime (21231110521) 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, 1187516 + ... + 1205261.

It is an arithmetic number, because the mean of its divisors is an integer number (2799550260).

Almost surely, 2^21231110321 is an apocalyptic number.

It is an amenable number.

21231110321 is a deficient number, since it is larger than the sum of its proper divisors (1165291759).

21231110321 is a wasteful number, since it uses less digits than its factorization.

21231110321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2393263.

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 21231110321 its reverse (12301113212), we get a palindrome (33532223533).

The spelling of 21231110321 in words is "twenty-one billion, two hundred thirty-one million, one hundred ten thousand, three hundred twenty-one".