18001938 has 16 divisors (see below), whose sum is σ = 36187200. Its totient is φ = 5970096.

The previous prime is 18001931. The next prime is 18001961. The reversal of 18001938 is 83910081.

It is not an unprimeable number, because it can be changed into a prime (18001931) 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, 6345 + ... + 8732.

It is an arithmetic number, because the mean of its divisors is an integer number (2261700).

Almost surely, 2^18001938 is an apocalyptic number.

18001938 is an abundant number, since it is smaller than the sum of its proper divisors (18185262).

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

18001938 is a wasteful number, since it uses less digits than its factorization.

18001938 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15281.

The product of its (nonzero) digits is 1728, while the sum is 30.

The square root of 18001938 is about 4242.8690764623. The cubic root of 18001938 is about 262.0835446330.

The spelling of 18001938 in words is "eighteen million, one thousand, nine hundred thirty-eight".