21324044 has 48 divisors (see below), whose sum is σ = 44352000. Its totient is φ = 8781696.

The previous prime is 21324031. The next prime is 21324047. The reversal of 21324044 is 44042312.

It is not an unprimeable number, because it can be changed into a prime (21324047) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 107057 + ... + 107255.

It is an arithmetic number, because the mean of its divisors is an integer number (924000).

Almost surely, 2^21324044 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21324044, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22176000).

21324044 is an abundant number, since it is smaller than the sum of its proper divisors (23027956).

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

21324044 is a wasteful number, since it uses less digits than its factorization.

21324044 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 342 (or 340 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 20.

The square root of 21324044 is about 4617.7964441928. The cubic root of 21324044 is about 277.3042484959.

Adding to 21324044 its reverse (44042312), we get a palindrome (65366356).

The spelling of 21324044 in words is "twenty-one million, three hundred twenty-four thousand, forty-four".