18638000 has 40 divisors (see below), whose sum is σ = 45071520. Its totient is φ = 7454400.

The previous prime is 18637999. The next prime is 18638003. The reversal of 18638000 is 83681.

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18638003) 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, 2660 + ... + 6659.

It is an arithmetic number, because the mean of its divisors is an integer number (1126788).

Almost surely, 2^18638000 is an apocalyptic number.

18638000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18638000 is an abundant number, since it is smaller than the sum of its proper divisors (26433520).

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

18638000 is an equidigital number, since it uses as much as digits as its factorization.

18638000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9342 (or 9326 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 26.

The square root of 18638000 is about 4317.1750022439. The cubic root of 18638000 is about 265.1346177317.

The spelling of 18638000 in words is "eighteen million, six hundred thirty-eight thousand".