21813040823 has 8 divisors (see below), whose sum is σ = 24951397248. Its totient is φ = 18680236344.

The previous prime is 21813040811. The next prime is 21813040831. The reversal of 21813040823 is 32804031812.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21813040823 - 2⁴ = 21813040807 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21813040823.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21813040853) 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, 1379561 + ... + 1395282.

It is an arithmetic number, because the mean of its divisors is an integer number (3118924656).

Almost surely, 2^21813040823 is an apocalyptic number.

21813040823 is a deficient number, since it is larger than the sum of its proper divisors (3138356425).

21813040823 is a wasteful number, since it uses less digits than its factorization.

21813040823 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2775973.

The product of its (nonzero) digits is 9216, while the sum is 32.

The spelling of 21813040823 in words is "twenty-one billion, eight hundred thirteen million, forty thousand, eight hundred twenty-three".