21304244 has 24 divisors (see below), whose sum is σ = 42265440. Its totient is φ = 9314784.

The previous prime is 21304237. The next prime is 21304253. The reversal of 21304244 is 44240312.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9794 + ... + 11769.

It is an arithmetic number, because the mean of its divisors is an integer number (1761060).

Almost surely, 2^21304244 is an apocalyptic number.

It is an amenable number.

21304244 is a deficient number, since it is larger than the sum of its proper divisors (20961196).

21304244 is a wasteful number, since it uses less digits than its factorization.

21304244 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21599 (or 21597 counting only the distinct ones).

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

The square root of 21304244 is about 4615.6520666099. The cubic root of 21304244 is about 277.2183935427.

Adding to 21304244 its reverse (44240312), we get a palindrome (65544556).

The spelling of 21304244 in words is "twenty-one million, three hundred four thousand, two hundred forty-four".