18165320 has 32 divisors (see below), whose sum is σ = 41438520. Its totient is φ = 7165440.

The previous prime is 18165319. The next prime is 18165347. The reversal of 18165320 is 2356181.

It can be written as a sum of positive squares in 4 ways, for example, as 10201636 + 7963684 = 3194^2 + 2822^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 18165320.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 191 + ... + 6030.

Almost surely, 2^18165320 is an apocalyptic number.

18165320 is a gapful number since it is divisible by the number (10) 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 18165320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20719260).

18165320 is an abundant number, since it is smaller than the sum of its proper divisors (23273200).

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

18165320 is a wasteful number, since it uses less digits than its factorization.

18165320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6305 (or 6301 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 26.

The square root of 18165320 is about 4262.0793047526. The cubic root of 18165320 is about 262.8740306685.

The spelling of 18165320 in words is "eighteen million, one hundred sixty-five thousand, three hundred twenty".