21756523204 has 12 divisors (see below), whose sum is σ = 41002678444. Its totient is φ = 10041472224.

The previous prime is 21756523183. The next prime is 21756523207. The reversal of 21756523204 is 40232565712.

It can be written as a sum of positive squares in 2 ways, for example, as 14895714304 + 6860808900 = 122048^2 + 82830^2 .

It is not an unprimeable number, because it can be changed into a prime (21756523207) 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 3 ways as a sum of consecutive naturals, for example, 209197287 + ... + 209197390.

Almost surely, 2^21756523204 is an apocalyptic number.

It is an amenable number.

21756523204 is a deficient number, since it is larger than the sum of its proper divisors (19246155240).

21756523204 is a wasteful number, since it uses less digits than its factorization.

21756523204 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 418394694 (or 418394692 counting only the distinct ones).

The product of its (nonzero) digits is 100800, while the sum is 37.

The spelling of 21756523204 in words is "twenty-one billion, seven hundred fifty-six million, five hundred twenty-three thousand, two hundred four".