21308065504 has 48 divisors (see below), whose sum is σ = 45793505520. Its totient is φ = 9679221760.

The previous prime is 21308065483. The next prime is 21308065507. The reversal of 21308065504 is 40556080312.

It is a self number, because there is not a number n which added to its sum of digits gives 21308065504.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21308065507) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 549012 + ... + 586540.

It is an arithmetic number, because the mean of its divisors is an integer number (954031365).

Almost surely, 2^21308065504 is an apocalyptic number.

It is an amenable number.

21308065504 is an abundant number, since it is smaller than the sum of its proper divisors (24485440016).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21308065504 is a wasteful number, since it uses less digits than its factorization.

21308065504 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39163 (or 39155 counting only the distinct ones).

The product of its (nonzero) digits is 28800, while the sum is 34.

The spelling of 21308065504 in words is "twenty-one billion, three hundred eight million, sixty-five thousand, five hundred four".