21321312023 has 16 divisors (see below), whose sum is σ = 24489104640. Its totient is φ = 18358876800.

The previous prime is 21321312013. The next prime is 21321312031. The reversal of 21321312023 is 32021312312.

It is not a de Polignac number, because 21321312023 - 2⁴ = 21321312007 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21321311986 and 21321312004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21321312013) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1366838 + ... + 1382348.

It is an arithmetic number, because the mean of its divisors is an integer number (1530569040).

Almost surely, 2^21321312023 is an apocalyptic number.

21321312023 is a deficient number, since it is larger than the sum of its proper divisors (3167792617).

21321312023 is a wasteful number, since it uses less digits than its factorization.

21321312023 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22118.

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

Adding to 21321312023 its reverse (32021312312), we get a palindrome (53342624335).

The spelling of 21321312023 in words is "twenty-one billion, three hundred twenty-one million, three hundred twelve thousand, twenty-three".