18989394 has 16 divisors (see below), whose sum is σ = 38193120. Its totient is φ = 6294080.

The previous prime is 18989393. The next prime is 18989401. The reversal of 18989394 is 49398981.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (18989393) 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, 7767 + ... + 9914.

It is an arithmetic number, because the mean of its divisors is an integer number (2387070).

Almost surely, 2^18989394 is an apocalyptic number.

18989394 is an abundant number, since it is smaller than the sum of its proper divisors (19203726).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18989394 is a wasteful number, since it uses less digits than its factorization.

18989394 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17865.

The product of its digits is 559872, while the sum is 51.

The square root of 18989394 is about 4357.6821820780. The cubic root of 18989394 is about 266.7905046345.

The spelling of 18989394 in words is "eighteen million, nine hundred eighty-nine thousand, three hundred ninety-four".