18381400 has 48 divisors (see below), whose sum is σ = 43356600. Its totient is φ = 7246080.

The previous prime is 18381397. The next prime is 18381457. The reversal of 18381400 is 418381.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is a congruent number.

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 11 ways as a sum of consecutive naturals, for example, 13971 + ... + 15229.

Almost surely, 2^18381400 is an apocalyptic number.

18381400 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18381400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21678300).

18381400 is an abundant number, since it is smaller than the sum of its proper divisors (24975200).

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

18381400 is a wasteful number, since it uses less digits than its factorization.

18381400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1348 (or 1339 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 25.

The square root of 18381400 is about 4287.3534960393. The cubic root of 18381400 is about 263.9122374334.

Adding to 18381400 its reverse (418381), we get a palindrome (18799781).

It can be divided in two parts, 18381 and 400, that added together give a palindrome (18781).

The spelling of 18381400 in words is "eighteen million, three hundred eighty-one thousand, four hundred".