18831989 has 8 divisors (see below), whose sum is σ = 20617632. Its totient is φ = 17058640.

The previous prime is 18831959. The next prime is 18832003. The reversal of 18831989 is 98913881.

It is a happy number.

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 18831989 - 2²⁰ = 17783413 is a prime.

It is a super-2 number, since 2×18831989² = 709287619392242, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18831959) 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, 302 + ... + 6144.

It is an arithmetic number, because the mean of its divisors is an integer number (2577204).

Almost surely, 2^18831989 is an apocalyptic number.

It is an amenable number.

18831989 is a deficient number, since it is larger than the sum of its proper divisors (1785643).

18831989 is a wasteful number, since it uses less digits than its factorization.

18831989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6147.

The product of its digits is 124416, while the sum is 47.

The square root of 18831989 is about 4339.5839662346. The cubic root of 18831989 is about 266.0513073058.

The spelling of 18831989 in words is "eighteen million, eight hundred thirty-one thousand, nine hundred eighty-nine".