18989568 has 120 divisors (see below), whose sum is σ = 59207148. Its totient is φ = 5824512.

The previous prime is 18989567. The next prime is 18989587. The reversal of 18989568 is 86598981.

It can be written as a sum of positive squares in 2 ways, for example, as 15116544 + 3873024 = 3888^2 + 1968^2 .

It is not an unprimeable number, because it can be changed into a prime (18989567) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 59746 + ... + 60062.

Almost surely, 2^18989568 is an apocalyptic number.

18989568 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18989568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29603574).

18989568 is an abundant number, since it is smaller than the sum of its proper divisors (40217580).

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

18989568 is a wasteful number, since it uses less digits than its factorization.

18989568 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 354 (or 335 counting only the distinct ones).

The product of its digits is 1244160, while the sum is 54.

The square root of 18989568 is about 4357.7021467741. The cubic root of 18989568 is about 266.7913195000.

The spelling of 18989568 in words is "eighteen million, nine hundred eighty-nine thousand, five hundred sixty-eight".