18438828 has 24 divisors (see below), whose sum is σ = 43093680. Its totient is φ = 6136320.

The previous prime is 18438821. The next prime is 18438841. The reversal of 18438828 is 82883481.

It is a self number, because there is not a number n which added to its sum of digits gives 18438828.

It is not an unprimeable number, because it can be changed into a prime (18438821) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12868 + ... + 14228.

It is an arithmetic number, because the mean of its divisors is an integer number (1795570).

Almost surely, 2^18438828 is an apocalyptic number.

It is an amenable number.

18438828 is an abundant number, since it is smaller than the sum of its proper divisors (24654852).

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

18438828 is a wasteful number, since it uses less digits than its factorization.

18438828 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2497 (or 2495 counting only the distinct ones).

The product of its digits is 98304, while the sum is 42.

The square root of 18438828 is about 4294.0456448436. The cubic root of 18438828 is about 264.1867938813.

The spelling of 18438828 in words is "eighteen million, four hundred thirty-eight thousand, eight hundred twenty-eight".