21042738884 has 12 divisors (see below), whose sum is σ = 37343452608. Its totient is φ = 10373181000.

The previous prime is 21042738793. The next prime is 21042738889. The reversal of 21042738884 is 48883724012.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21042738889) 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 3 ways as a sum of consecutive naturals, for example, 37046792 + ... + 37047359.

It is an arithmetic number, because the mean of its divisors is an integer number (3111954384).

Almost surely, 2^21042738884 is an apocalyptic number.

It is an amenable number.

21042738884 is a deficient number, since it is larger than the sum of its proper divisors (16300713724).

21042738884 is a wasteful number, since it uses less digits than its factorization.

21042738884 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74094226 (or 74094224 counting only the distinct ones).

The product of its (nonzero) digits is 688128, while the sum is 47.

The spelling of 21042738884 in words is "twenty-one billion, forty-two million, seven hundred thirty-eight thousand, eight hundred eighty-four".