21844959 has 4 divisors (see below), whose sum is σ = 29126616. Its totient is φ = 14563304.

The previous prime is 21844939. The next prime is 21844967. The reversal of 21844959 is 95944812.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21844959 - 2⁷ = 21844831 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21844959.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21844919) 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, 3640824 + ... + 3640829.

It is an arithmetic number, because the mean of its divisors is an integer number (7281654).

Almost surely, 2^21844959 is an apocalyptic number.

21844959 is a deficient number, since it is larger than the sum of its proper divisors (7281657).

21844959 is an equidigital number, since it uses as much as digits as its factorization.

21844959 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7281656.

The product of its digits is 103680, while the sum is 42.

The square root of 21844959 is about 4673.8591121257. The cubic root of 21844959 is about 279.5441519766.

The spelling of 21844959 in words is "twenty-one million, eight hundred forty-four thousand, nine hundred fifty-nine".