20812089 has 4 divisors (see below), whose sum is σ = 27749456. Its totient is φ = 13874724.

The previous prime is 20812039. The next prime is 20812091. The reversal of 20812089 is 98021802.

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 20812089 - 2²⁴ = 4034873 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20812039) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3468679 + ... + 3468684.

It is an arithmetic number, because the mean of its divisors is an integer number (6937364).

Almost surely, 2^20812089 is an apocalyptic number.

It is an amenable number.

20812089 is a deficient number, since it is larger than the sum of its proper divisors (6937367).

20812089 is an equidigital number, since it uses as much as digits as its factorization.

20812089 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6937366.

The product of its (nonzero) digits is 2304, while the sum is 30.

The square root of 20812089 is about 4562.0268521788. The cubic root of 20812089 is about 275.0670426074.

The spelling of 20812089 in words is "twenty million, eight hundred twelve thousand, eighty-nine".