20188889 has 8 divisors (see below), whose sum is σ = 23127168. Its totient is φ = 17264160.

The previous prime is 20188879. The next prime is 20188907. The reversal of 20188889 is 98888102.

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

It is a cyclic number.

It is not a de Polignac number, because 20188889 - 2⁸ = 20188633 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20188829) 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, 44 + ... + 6354.

It is an arithmetic number, because the mean of its divisors is an integer number (2890896).

Almost surely, 2^20188889 is an apocalyptic number.

It is an amenable number.

20188889 is a deficient number, since it is larger than the sum of its proper divisors (2938279).

20188889 is an equidigital number, since it uses as much as digits as its factorization.

20188889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6775.

The product of its (nonzero) digits is 73728, while the sum is 44.

The square root of 20188889 is about 4493.2047582989. The cubic root of 20188889 is about 272.2936248504.

The spelling of 20188889 in words is "twenty million, one hundred eighty-eight thousand, eight hundred eighty-nine".