21838964 has 24 divisors (see below), whose sum is σ = 43807680. Its totient is φ = 9331776.

The previous prime is 21838963. The next prime is 21838967. The reversal of 21838964 is 46983812.

It is a Smith number, since the sum of its digits (41) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21838963) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10499 + ... + 12405.

It is an arithmetic number, because the mean of its divisors is an integer number (1825320).

Almost surely, 2^21838964 is an apocalyptic number.

It is an amenable number.

21838964 is an abundant number, since it is smaller than the sum of its proper divisors (21968716).

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

21838964 is a wasteful number, since it uses less digits than its factorization.

21838964 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2327 (or 2325 counting only the distinct ones).

The product of its digits is 82944, while the sum is 41.

The square root of 21838964 is about 4673.2177351371. The cubic root of 21838964 is about 279.5185774948.

The spelling of 21838964 in words is "twenty-one million, eight hundred thirty-eight thousand, nine hundred sixty-four".