18406240 has 96 divisors (see below), whose sum is σ = 47192544. Its totient is φ = 6758400.

The previous prime is 18406229. The next prime is 18406319. The reversal of 18406240 is 4260481.

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 15 ways as a sum of consecutive naturals, for example, 182190 + ... + 182290.

It is an arithmetic number, because the mean of its divisors is an integer number (491589).

Almost surely, 2^18406240 is an apocalyptic number.

18406240 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 18406240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23596272).

18406240 is an abundant number, since it is smaller than the sum of its proper divisors (28786304).

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

18406240 is a wasteful number, since it uses less digits than its factorization.

18406240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 200 (or 192 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 25.

The square root of 18406240 is about 4290.2494099994. The cubic root of 18406240 is about 264.0310646029.

The spelling of 18406240 in words is "eighteen million, four hundred six thousand, two hundred forty".