18028240 has 20 divisors (see below), whose sum is σ = 41915844. Its totient is φ = 7211264.

The previous prime is 18028237. The next prime is 18028247. The reversal of 18028240 is 4282081.

It can be written as a sum of positive squares in 2 ways, for example, as 8737936 + 9290304 = 2956^2 + 3048^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18028247) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 112597 + ... + 112756.

Almost surely, 2^18028240 is an apocalyptic number.

18028240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18028240 is an abundant number, since it is smaller than the sum of its proper divisors (23887604).

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

18028240 is a wasteful number, since it uses less digits than its factorization.

18028240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 225366 (or 225360 counting only the distinct ones).

The product of its (nonzero) digits is 1024, while the sum is 25.

The square root of 18028240 is about 4245.9674986980. The cubic root of 18028240 is about 262.2111228770.

The spelling of 18028240 in words is "eighteen million, twenty-eight thousand, two hundred forty".