20211089 has 4 divisors (see below), whose sum is σ = 21089856. Its totient is φ = 19332324.

The previous prime is 20211077. The next prime is 20211097. The reversal of 20211089 is 98011202.

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 20211089 - 2²⁰ = 19162513 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (23), and also a Moran number because the ratio is a prime number: 878743 = 20211089 / (2 + 0 + 2 + 1 + 1 + 0 + 8 + 9).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20216089) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 439349 + ... + 439394.

It is an arithmetic number, because the mean of its divisors is an integer number (5272464).

Almost surely, 2^20211089 is an apocalyptic number.

It is an amenable number.

20211089 is a deficient number, since it is larger than the sum of its proper divisors (878767).

20211089 is an equidigital number, since it uses as much as digits as its factorization.

20211089 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 878766.

The product of its (nonzero) digits is 288, while the sum is 23.

The square root of 20211089 is about 4495.6744766497. The cubic root of 20211089 is about 272.3933943181.

The spelling of 20211089 in words is "twenty million, two hundred eleven thousand, eighty-nine".