23403000021 has 4 divisors (see below), whose sum is σ = 31204000032. Its totient is φ = 15602000012.

The previous prime is 23403000013. The next prime is 23403000059. The reversal of 23403000021 is 12000030432.

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 23403000021 - 2³ = 23403000013 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23403000011) 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, 3900500001 + ... + 3900500006.

It is an arithmetic number, because the mean of its divisors is an integer number (7801000008).

Almost surely, 2^23403000021 is an apocalyptic number.

It is an amenable number.

23403000021 is a deficient number, since it is larger than the sum of its proper divisors (7801000011).

23403000021 is an equidigital number, since it uses as much as digits as its factorization.

23403000021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7801000010.

The product of its (nonzero) digits is 144, while the sum is 15.

Adding to 23403000021 its reverse (12000030432), we get a palindrome (35403030453).

The spelling of 23403000021 in words is "twenty-three billion, four hundred three million, twenty-one", and thus it is an aban number.