18168644 has 12 divisors (see below), whose sum is σ = 34241004. Its totient is φ = 8385504.

The previous prime is 18168611. The next prime is 18168659. The reversal of 18168644 is 44686181.

It can be written as a sum of positive squares in 2 ways, for example, as 6002500 + 12166144 = 2450^2 + 3488^2 .

It is a junction number, because it is equal to n+sod(n) for n = 18168598 and 18168607.

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 3 ways as a sum of consecutive naturals, for example, 174647 + ... + 174750.

It is an arithmetic number, because the mean of its divisors is an integer number (2853417).

Almost surely, 2^18168644 is an apocalyptic number.

It is an amenable number.

18168644 is a deficient number, since it is larger than the sum of its proper divisors (16072360).

18168644 is a wasteful number, since it uses less digits than its factorization.

18168644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 349414 (or 349412 counting only the distinct ones).

The product of its digits is 36864, while the sum is 38.

The square root of 18168644 is about 4262.4692374256. The cubic root of 18168644 is about 262.8900637834.

The spelling of 18168644 in words is "eighteen million, one hundred sixty-eight thousand, six hundred forty-four".