21523813928 has 16 divisors (see below), whose sum is σ = 42481212000. Its totient is φ = 10195490736.

The previous prime is 21523813907. The next prime is 21523813943. The reversal of 21523813928 is 82931832512.

It is a Smith number, since the sum of its digits (44) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 70801868 + ... + 70802171.

It is an arithmetic number, because the mean of its divisors is an integer number (2655075750).

Almost surely, 2^21523813928 is an apocalyptic number.

It is an amenable number.

21523813928 is a deficient number, since it is larger than the sum of its proper divisors (20957398072).

21523813928 is a wasteful number, since it uses less digits than its factorization.

21523813928 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 141604064 (or 141604060 counting only the distinct ones).

The product of its digits is 207360, while the sum is 44.

The spelling of 21523813928 in words is "twenty-one billion, five hundred twenty-three million, eight hundred thirteen thousand, nine hundred twenty-eight".