21444003 has 12 divisors (see below), whose sum is σ = 35399728. Its totient is φ = 12253680.

The previous prime is 21443999. The next prime is 21444011. The reversal of 21444003 is 30044412.

It is not a de Polignac number, because 21444003 - 2² = 21443999 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21444023) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 170128 + ... + 170253.

Almost surely, 2^21444003 is an apocalyptic number.

21444003 is a deficient number, since it is larger than the sum of its proper divisors (13955725).

21444003 is a wasteful number, since it uses less digits than its factorization.

21444003 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 340394 (or 340391 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 18.

The square root of 21444003 is about 4630.7669991050. The cubic root of 21444003 is about 277.8232706942.

Adding to 21444003 its reverse (30044412), we get a palindrome (51488415).

The spelling of 21444003 in words is "twenty-one million, four hundred forty-four thousand, three".