18000438 has 8 divisors (see below), whose sum is σ = 36000888. Its totient is φ = 6000144.

The previous prime is 18000407. The next prime is 18000439. The reversal of 18000438 is 83400081.

It is a sphenic number, since it is the product of 3 distinct primes.

18000438 is an admirable number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18000439) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1500031 + ... + 1500042.

It is an arithmetic number, because the mean of its divisors is an integer number (4500111).

Almost surely, 2^18000438 is an apocalyptic number.

18000438 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

18000438 is a wasteful number, since it uses less digits than its factorization.

18000438 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3000078.

The product of its (nonzero) digits is 768, while the sum is 24.

The square root of 18000438 is about 4242.6923056003. The cubic root of 18000438 is about 262.0762651161.

The spelling of 18000438 in words is "eighteen million, four hundred thirty-eight", and thus it is an aban number.