21844618 has 16 divisors (see below), whose sum is σ = 34292160. Its totient is φ = 10416736.

The previous prime is 21844607. The next prime is 21844621. The reversal of 21844618 is 81644812.

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 7 ways as a sum of consecutive naturals, for example, 26598 + ... + 27406.

It is an arithmetic number, because the mean of its divisors is an integer number (2143260).

Almost surely, 2^21844618 is an apocalyptic number.

21844618 is a deficient number, since it is larger than the sum of its proper divisors (12447542).

21844618 is a wasteful number, since it uses less digits than its factorization.

21844618 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1421.

The product of its digits is 12288, while the sum is 34.

The square root of 21844618 is about 4673.8226324926. The cubic root of 21844618 is about 279.5426974068.

The spelling of 21844618 in words is "twenty-one million, eight hundred forty-four thousand, six hundred eighteen".