18938 has 8 divisors (see below), whose sum is σ = 30132. Its totient is φ = 8896.

The previous prime is 18919. The next prime is 18947. The reversal of 18938 is 83981.

It is a happy number.

18938 is nontrivially palindromic in base 9.

It can be written as a sum of positive squares in 2 ways, for example, as 18769 + 169 = 137^2 + 13^2 .

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

Its product of digits (1728) is a multiple of the sum of its prime divisors (576).

It is a self number, because there is not a number n which added to its sum of digits gives 18938.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 245 + ... + 312.

2¹⁸⁹³⁸ is an apocalyptic number.

18938 is a deficient number, since it is larger than the sum of its proper divisors (11194).

18938 is a wasteful number, since it uses less digits than its factorization.

18938 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 576.

The product of its digits is 1728, while the sum is 29.

The square root of 18938 is about 137.6154061143. The cubic root of 18938 is about 26.6549601394.

The spelling of 18938 in words is "eighteen thousand, nine hundred thirty-eight".