21229444 has 12 divisors (see below), whose sum is σ = 38015824. Its totient is φ = 10367784.

The previous prime is 21229409. The next prime is 21229463. The reversal of 21229444 is 44492212.

It is a hoax number, since the sum of its digits (28) coincides with the sum of the digits of its distinct prime factors.

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, 61542 + ... + 61885.

Almost surely, 2^21229444 is an apocalyptic number.

It is an amenable number.

21229444 is a deficient number, since it is larger than the sum of its proper divisors (16786380).

21229444 is a wasteful number, since it uses less digits than its factorization.

21229444 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 123474 (or 123472 counting only the distinct ones).

The product of its digits is 4608, while the sum is 28.

The square root of 21229444 is about 4607.5420779413. The cubic root of 21229444 is about 276.8935716982.

The spelling of 21229444 in words is "twenty-one million, two hundred twenty-nine thousand, four hundred forty-four".