18904989 has 8 divisors (see below), whose sum is σ = 25339392. Its totient is φ = 12536960.

The previous prime is 18904987. The next prime is 18904997. The reversal of 18904989 is 98940981.

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 18904989 - 2¹ = 18904987 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18904987) 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 7 ways as a sum of consecutive naturals, for example, 15924 + ... + 17069.

It is an arithmetic number, because the mean of its divisors is an integer number (3167424).

Almost surely, 2^18904989 is an apocalyptic number.

It is an amenable number.

18904989 is a deficient number, since it is larger than the sum of its proper divisors (6434403).

18904989 is a wasteful number, since it uses less digits than its factorization.

18904989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33187.

The product of its (nonzero) digits is 186624, while the sum is 48.

The square root of 18904989 is about 4347.9867755089. The cubic root of 18904989 is about 266.3946363077.

The spelling of 18904989 in words is "eighteen million, nine hundred four thousand, nine hundred eighty-nine".