18388 has 6 divisors (see below), whose sum is σ = 32186. Its totient is φ = 9192.

The previous prime is 18379. The next prime is 18397. The reversal of 18388 is 88381.

It is an interprime number because it is at equal distance from previous prime (18379) and next prime (18397).

It can be written as a sum of positive squares in only one way, i.e., 11664 + 6724 = 108^2 + 82^2 .

It is a plaindrome in base 15.

It is a congruent number.

It is an unprimeable number.

18388 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2295 + ... + 2302.

2¹⁸³⁸⁸ is an apocalyptic number.

It is an amenable number.

18388 is a deficient number, since it is larger than the sum of its proper divisors (13798).

18388 is a wasteful number, since it uses less digits than its factorization.

18388 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4601 (or 4599 counting only the distinct ones).

The product of its digits is 1536, while the sum is 28.

The square root of 18388 is about 135.6023598615. The cubic root of 18388 is about 26.3943820308.

It can be divided in two parts, 18 and 388, that added together give a triangular number (406 = T₂₈).

The spelling of 18388 in words is "eighteen thousand, three hundred eighty-eight".