18193938 has 32 divisors (see below), whose sum is σ = 42007680. Its totient is φ = 5145600.

The previous prime is 18193913. The next prime is 18193957. The reversal of 18193938 is 83939181.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a self number, because there is not a number n which added to its sum of digits gives 18193938.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 2098 + ... + 6386.

It is an arithmetic number, because the mean of its divisors is an integer number (1312740).

Almost surely, 2^18193938 is an apocalyptic number.

18193938 is an abundant number, since it is smaller than the sum of its proper divisors (23813742).

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

18193938 is a wasteful number, since it uses less digits than its factorization.

18193938 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4402.

The product of its digits is 46656, while the sum is 42.

The square root of 18193938 is about 4265.4352650111. The cubic root of 18193938 is about 263.0120038664.

The spelling of 18193938 in words is "eighteen million, one hundred ninety-three thousand, nine hundred thirty-eight".