18032640 has 96 divisors (see below), whose sum is σ = 57788640. Its totient is φ = 4800512.

The previous prime is 18032587. The next prime is 18032647. The reversal of 18032640 is 4623081.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (96).

It is a super-2 number, since 2×18032640² = 650352210739200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 18032640.

It is not an unprimeable number, because it can be changed into a prime (18032647) 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, 30427 + ... + 31013.

It is an arithmetic number, because the mean of its divisors is an integer number (601965).

Almost surely, 2^18032640 is an apocalyptic number.

18032640 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 18032640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28894320).

18032640 is an abundant number, since it is smaller than the sum of its proper divisors (39756000).

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

18032640 is an equidigital number, since it uses as much as digits as its factorization.

18032640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 617 (or 597 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 24.

The square root of 18032640 is about 4246.4856057686. The cubic root of 18032640 is about 262.2324530252.

The spelling of 18032640 in words is "eighteen million, thirty-two thousand, six hundred forty".