18993204 has 90 divisors (see below), whose sum is σ = 52146402. Its totient is φ = 6026400.

The previous prime is 18993203. The next prime is 18993211. The reversal of 18993204 is 40239981.

It can be written as a sum of positive squares in only one way, i.e., 11209104 + 7784100 = 3348^2 + 2790^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18993203) by changing a digit.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 311334 + ... + 311394.

Almost surely, 2^18993204 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18993204, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26073201).

18993204 is an abundant number, since it is smaller than the sum of its proper divisors (33153198).

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

18993204 is a wasteful number, since it uses less digits than its factorization.

18993204 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 139 (or 97 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 36.

The square root of 18993204 is about 4358.1193191559. The cubic root of 18993204 is about 266.8083462403.

The spelling of 18993204 in words is "eighteen million, nine hundred ninety-three thousand, two hundred four".