21031232321 has 8 divisors (see below), whose sum is σ = 24292760544. Its totient is φ = 17994637120.

The previous prime is 21031232293. The next prime is 21031232347. The reversal of 21031232321 is 12323213012.

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 21031232321 - 2¹⁰ = 21031231297 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21031232293 and 21031232302.

It is not an unprimeable number, because it can be changed into a prime (21031232921) 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, 56233055 + ... + 56233428.

It is an arithmetic number, because the mean of its divisors is an integer number (3036595068).

Almost surely, 2^21031232321 is an apocalyptic number.

It is an amenable number.

21031232321 is a deficient number, since it is larger than the sum of its proper divisors (3261528223).

21031232321 is a wasteful number, since it uses less digits than its factorization.

21031232321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 112466511.

The product of its (nonzero) digits is 432, while the sum is 20.

Adding to 21031232321 its reverse (12323213012), we get a palindrome (33354445333).

It can be divided in two parts, 21031 and 232321, that added together give a palindrome (253352).

The spelling of 21031232321 in words is "twenty-one billion, thirty-one million, two hundred thirty-two thousand, three hundred twenty-one".