18188889 has 8 divisors (see below), whose sum is σ = 24273120. Its totient is φ = 12115296.

The previous prime is 18188879. The next prime is 18188893. The reversal of 18188889 is 98888181.

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

It is not a de Polignac number, because 18188889 - 2⁵ = 18188857 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18188839) 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 7 ways as a sum of consecutive naturals, for example, 3142 + ... + 6800.

It is an arithmetic number, because the mean of its divisors is an integer number (3034140).

Almost surely, 2^18188889 is an apocalyptic number.

It is an amenable number.

18188889 is a deficient number, since it is larger than the sum of its proper divisors (6084231).

18188889 is a wasteful number, since it uses less digits than its factorization.

18188889 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5319.

The product of its digits is 294912, while the sum is 51.

The square root of 18188889 is about 4264.8433734429. The cubic root of 18188889 is about 262.9876721272.

The spelling of 18188889 in words is "eighteen million, one hundred eighty-eight thousand, eight hundred eighty-nine".