21323113021 has 4 divisors (see below), whose sum is σ = 24369272032. Its totient is φ = 18276954012.

The previous prime is 21323113001. The next prime is 21323113027. The reversal of 21323113021 is 12031132312.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21323113021 - 2⁵ = 21323112989 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21323113021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21323113027) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1523079495 + ... + 1523079508.

It is an arithmetic number, because the mean of its divisors is an integer number (6092318008).

Almost surely, 2^21323113021 is an apocalyptic number.

It is an amenable number.

21323113021 is a deficient number, since it is larger than the sum of its proper divisors (3046159011).

21323113021 is an equidigital number, since it uses as much as digits as its factorization.

21323113021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3046159010.

The product of its (nonzero) digits is 216, while the sum is 19.

Adding to 21323113021 its reverse (12031132312), we get a palindrome (33354245333).

The spelling of 21323113021 in words is "twenty-one billion, three hundred twenty-three million, one hundred thirteen thousand, twenty-one".