21444000044 has 24 divisors (see below), whose sum is σ = 39180395520. Its totient is φ = 10250120144.

The previous prime is 21444000043. The next prime is 21444000079. The reversal of 21444000044 is 44000044412.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a junction number, because it is equal to n+sod(n) for n = 21443999983 and 21444000019.

It is not an unprimeable number, because it can be changed into a prime (21444000043) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 103787 + ... + 231645.

It is an arithmetic number, because the mean of its divisors is an integer number (1632516480).

Almost surely, 2^21444000044 is an apocalyptic number.

It is an amenable number.

21444000044 is a deficient number, since it is larger than the sum of its proper divisors (17736395476).

21444000044 is a wasteful number, since it uses less digits than its factorization.

21444000044 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129709 (or 129707 counting only the distinct ones).

The product of its (nonzero) digits is 2048, while the sum is 23.

Adding to 21444000044 its reverse (44000044412), we get a palindrome (65444044456).

The spelling of 21444000044 in words is "twenty-one billion, four hundred forty-four million, forty-four", and thus it is an aban number.