21232810729536 has 56 divisors (see below), whose sum is σ = 64203975305280. Its totient is φ = 6066517350912.

The previous prime is 21232810729513. The next prime is 21232810729601. The reversal of 21232810729536 is 63592701823212.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (56).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7899109791 + ... + 7899112478.

Almost surely, 2^{21232810729536} is an apocalyptic number.

It is an amenable number.

21232810729536 is an abundant number, since it is smaller than the sum of its proper divisors (42971164575744).

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

21232810729536 is a wasteful number, since it uses less digits than its factorization.

21232810729536 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15798222291 (or 15798222281 counting only the distinct ones).

The product of its (nonzero) digits is 2177280, while the sum is 51.

The spelling of 21232810729536 in words is "twenty-one trillion, two hundred thirty-two billion, eight hundred ten million, seven hundred twenty-nine thousand, five hundred thirty-six".