20231813 has 4 divisors (see below), whose sum is σ = 23122080. Its totient is φ = 17341548.

The previous prime is 20231807. The next prime is 20231839. The reversal of 20231813 is 31813202.

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 not a de Polignac number, because 20231813 - 2⁸ = 20231557 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20231843) 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, 1445123 + ... + 1445136.

It is an arithmetic number, because the mean of its divisors is an integer number (5780520).

Almost surely, 2^20231813 is an apocalyptic number.

It is an amenable number.

20231813 is a deficient number, since it is larger than the sum of its proper divisors (2890267).

20231813 is an equidigital number, since it uses as much as digits as its factorization.

20231813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2890266.

The product of its (nonzero) digits is 288, while the sum is 20.

The square root of 20231813 is about 4497.9787682914. The cubic root of 20231813 is about 272.4864645523.

The spelling of 20231813 in words is "twenty million, two hundred thirty-one thousand, eight hundred thirteen".