21444470 has 16 divisors (see below), whose sum is σ = 38834208. Its totient is φ = 8525760.

The previous prime is 21444457. The next prime is 21444481. The reversal of 21444470 is 7444412.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4751 + ... + 8090.

It is an arithmetic number, because the mean of its divisors is an integer number (2427138).

Almost surely, 2^21444470 is an apocalyptic number.

21444470 is a deficient number, since it is larger than the sum of its proper divisors (17389738).

21444470 is a wasteful number, since it uses less digits than its factorization.

21444470 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13015.

The product of its (nonzero) digits is 3584, while the sum is 26.

The square root of 21444470 is about 4630.8174224428. The cubic root of 21444470 is about 277.8252874589.

Adding to 21444470 its reverse (7444412), we get a palindrome (28888882).

The spelling of 21444470 in words is "twenty-one million, four hundred forty-four thousand, four hundred seventy".