21364720740576 has 72 divisors (see below), whose sum is σ = 61751923420824. Its totient is φ = 7004826466560.

The previous prime is 21364720740551. The next prime is 21364720740577. The reversal of 21364720740576 is 67504702746312.

21364720740576 is a `hidden beast` number, since 2 + 1 + 3 + 6 + 4 + 7 + 20 + 7 + 40 + 576 = 666.

It is a tau number, because it is divible by the number of its divisors (72).

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21364720740577) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 608040286 + ... + 608075421.

It is an arithmetic number, because the mean of its divisors is an integer number (857665603067).

Almost surely, 2^{21364720740576} is an apocalyptic number.

It is an amenable number.

21364720740576 is an abundant number, since it is smaller than the sum of its proper divisors (40387202680248).

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

21364720740576 is a wasteful number, since it uses less digits than its factorization.

21364720740576 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1216115784 (or 1216115773 counting only the distinct ones).

The product of its (nonzero) digits is 11854080, while the sum is 54.

The spelling of 21364720740576 in words is "twenty-one trillion, three hundred sixty-four billion, seven hundred twenty million, seven hundred forty thousand, five hundred seventy-six".