21244304 has 10 divisors (see below), whose sum is σ = 41160870. Its totient is φ = 10622144.

The previous prime is 21244303. The next prime is 21244309. The reversal of 21244304 is 40344212.

It can be written as a sum of positive squares in only one way, i.e., 18835600 + 2408704 = 4340^2 + 1552^2 .

It is not an unprimeable number, because it can be changed into a prime (21244303) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 663869 + ... + 663900.

It is an arithmetic number, because the mean of its divisors is an integer number (4116087).

Almost surely, 2^21244304 is an apocalyptic number.

It is an amenable number.

21244304 is a deficient number, since it is larger than the sum of its proper divisors (19916566).

21244304 is a wasteful number, since it uses less digits than its factorization.

21244304 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1327777 (or 1327771 counting only the distinct ones).

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

The square root of 21244304 is about 4609.1543692960. The cubic root of 21244304 is about 276.9581624745.

Adding to 21244304 its reverse (40344212), we get a palindrome (61588516).

The spelling of 21244304 in words is "twenty-one million, two hundred forty-four thousand, three hundred four".