18664000 has 56 divisors (see below), whose sum is σ = 46241208. Its totient is φ = 7462400.

The previous prime is 18663941. The next prime is 18664007. The reversal of 18664000 is 46681.

It can be written as a sum of positive squares in 4 ways, for example, as 1557504 + 17106496 = 1248^2 + 4136^2 .

It is a Harshad number since it is a multiple of its sum of digits (25).

It is not an unprimeable number, because it can be changed into a prime (18664007) 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, 6834 + ... + 9166.

Almost surely, 2^18664000 is an apocalyptic number.

18664000 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 18664000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23120604).

18664000 is an abundant number, since it is smaller than the sum of its proper divisors (27577208).

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

18664000 is an equidigital number, since it uses as much as digits as its factorization.

18664000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2360 (or 2340 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 25.

The square root of 18664000 is about 4320.1851812162. The cubic root of 18664000 is about 265.2578479972.

The spelling of 18664000 in words is "eighteen million, six hundred sixty-four thousand".