18870889 has 4 divisors (see below), whose sum is σ = 18900100. Its totient is φ = 18841680.

The previous prime is 18870883. The next prime is 18870893. The reversal of 18870889 is 98807881.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 9211225 + 9659664 = 3035^2 + 3108^2 .

It is a cyclic number.

It is not a de Polignac number, because 18870889 - 2¹⁵ = 18838121 is a prime.

It is a super-2 number, since 2×18870889² = 712220903300642, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18870883) 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, 13614 + ... + 14935.

It is an arithmetic number, because the mean of its divisors is an integer number (4725025).

Almost surely, 2^18870889 is an apocalyptic number.

It is an amenable number.

18870889 is a deficient number, since it is larger than the sum of its proper divisors (29211).

18870889 is an equidigital number, since it uses as much as digits as its factorization.

18870889 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29210.

The product of its (nonzero) digits is 258048, while the sum is 49.

The square root of 18870889 is about 4344.0636505466. The cubic root of 18870889 is about 266.2343695410.

The spelling of 18870889 in words is "eighteen million, eight hundred seventy thousand, eight hundred eighty-nine".