18240856 has 8 divisors (see below), whose sum is σ = 34201620. Its totient is φ = 9120424.

The previous prime is 18240839. The next prime is 18240857. The reversal of 18240856 is 65804281.

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×18240856² = 665457655225472, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18240857) by changing a digit.

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 as a sum of consecutive naturals, namely, 1140046 + ... + 1140061.

Almost surely, 2^18240856 is an apocalyptic number.

It is an amenable number.

18240856 is a deficient number, since it is larger than the sum of its proper divisors (15960764).

18240856 is a wasteful number, since it uses less digits than its factorization.

18240856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2280113 (or 2280109 counting only the distinct ones).

The product of its (nonzero) digits is 15360, while the sum is 34.

The square root of 18240856 is about 4270.9315143186. The cubic root of 18240856 is about 263.2378923835.

The spelling of 18240856 in words is "eighteen million, two hundred forty thousand, eight hundred fifty-six".