21523774747872 has 96 divisors (see below), whose sum is σ = 60062436040320. Its totient is φ = 6729684595200.

The previous prime is 21523774747843. The next prime is 21523774747883. The reversal of 21523774747872 is 27874747732512.

It is a tau number, because it is divible by the number of its divisors (96).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 58233178 + ... + 58601625.

It is an arithmetic number, because the mean of its divisors is an integer number (625650375420).

Almost surely, 2^{21523774747872} is an apocalyptic number.

It is an amenable number.

21523774747872 is an abundant number, since it is smaller than the sum of its proper divisors (38538661292448).

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

21523774747872 is a wasteful number, since it uses less digits than its factorization.

21523774747872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 116834936 (or 116834928 counting only the distinct ones).

The product of its digits is 258155520, while the sum is 66.

The spelling of 21523774747872 in words is "twenty-one trillion, five hundred twenty-three billion, seven hundred seventy-four million, seven hundred forty-seven thousand, eight hundred seventy-two".