21323401423 has 4 divisors (see below), whose sum is σ = 21326189560. Its totient is φ = 21320613288.

The previous prime is 21323401391. The next prime is 21323401459. The reversal of 21323401423 is 32410432312.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21323401423 - 2⁵ = 21323401391 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21323404423) 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, 1382565 + ... + 1397902.

It is an arithmetic number, because the mean of its divisors is an integer number (5331547390).

Almost surely, 2^21323401423 is an apocalyptic number.

21323401423 is a deficient number, since it is larger than the sum of its proper divisors (2788137).

21323401423 is an equidigital number, since it uses as much as digits as its factorization.

21323401423 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2788136.

The product of its (nonzero) digits is 3456, while the sum is 25.

Adding to 21323401423 its reverse (32410432312), we get a palindrome (53733833735).

The spelling of 21323401423 in words is "twenty-one billion, three hundred twenty-three million, four hundred one thousand, four hundred twenty-three".