21044316 has 24 divisors (see below), whose sum is σ = 50302224. Its totient is φ = 6843520.

The previous prime is 21044311. The next prime is 21044341. The reversal of 21044316 is 61344012.

It is a junction number, because it is equal to n+sod(n) for n = 21044292 and 21044301.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21044311) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20895 + ... + 21878.

It is an arithmetic number, because the mean of its divisors is an integer number (2095926).

Almost surely, 2^21044316 is an apocalyptic number.

It is an amenable number.

21044316 is an abundant number, since it is smaller than the sum of its proper divisors (29257908).

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

21044316 is a wasteful number, since it uses less digits than its factorization.

21044316 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42821 (or 42819 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 21.

The square root of 21044316 is about 4587.4084187044. The cubic root of 21044316 is about 276.0863518923.

Adding to 21044316 its reverse (61344012), we get a palindrome (82388328).

The spelling of 21044316 in words is "twenty-one million, forty-four thousand, three hundred sixteen".