21224344 has 16 divisors (see below), whose sum is σ = 39909600. Its totient is φ = 10581792.

The previous prime is 21224323. The next prime is 21224351. The reversal of 21224344 is 44342212.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 679 + ... + 6550.

It is an arithmetic number, because the mean of its divisors is an integer number (2494350).

Almost surely, 2^21224344 is an apocalyptic number.

It is an amenable number.

21224344 is a deficient number, since it is larger than the sum of its proper divisors (18685256).

21224344 is a wasteful number, since it uses less digits than its factorization.

21224344 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7602 (or 7598 counting only the distinct ones).

The product of its digits is 1536, while the sum is 22.

The square root of 21224344 is about 4606.9886042837. The cubic root of 21224344 is about 276.8713969878.

Adding to 21224344 its reverse (44342212), we get a palindrome (65566556).

The spelling of 21224344 in words is "twenty-one million, two hundred twenty-four thousand, three hundred forty-four".