18321844 has 12 divisors (see below), whose sum is σ = 32094468. Its totient is φ = 9152000.

The previous prime is 18321839. The next prime is 18321847. The reversal of 18321844 is 44812381.

It can be written as a sum of positive squares in 2 ways, for example, as 15697444 + 2624400 = 3962^2 + 1620^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18321847) 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, 4974 + ... + 7834.

It is an arithmetic number, because the mean of its divisors is an integer number (2674539).

Almost surely, 2^18321844 is an apocalyptic number.

It is an amenable number.

18321844 is a deficient number, since it is larger than the sum of its proper divisors (13772624).

18321844 is a wasteful number, since it uses less digits than its factorization.

18321844 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4466 (or 4464 counting only the distinct ones).

The product of its digits is 6144, while the sum is 31.

The square root of 18321844 is about 4280.4023175398. The cubic root of 18321844 is about 263.6269025683.

The spelling of 18321844 in words is "eighteen million, three hundred twenty-one thousand, eight hundred forty-four".