18489816 has 32 divisors (see below), whose sum is σ = 51361200. Its totient is φ = 6163200.

The previous prime is 18489781. The next prime is 18489817. The reversal of 18489816 is 61898481.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18489817) 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, 42585 + ... + 43016.

Almost surely, 2^18489816 is an apocalyptic number.

It is an amenable number.

18489816 is an abundant number, since it is smaller than the sum of its proper divisors (32871384).

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

18489816 is a wasteful number, since it uses less digits than its factorization.

18489816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85616 (or 85606 counting only the distinct ones).

The product of its digits is 110592, while the sum is 45.

The square root of 18489816 is about 4299.9786045979. The cubic root of 18489816 is about 264.4300840907.

It can be divided in two parts, 1848 and 9816, that added together give a square (11664 = 108²).

The spelling of 18489816 in words is "eighteen million, four hundred eighty-nine thousand, eight hundred sixteen".