21715724448 has 72 divisors (see below), whose sum is σ = 67368109536. Its totient is φ = 6580521600.

The previous prime is 21715724441. The next prime is 21715724461. The reversal of 21715724448 is 84442751712.

21715724448 is a `hidden beast` number, since 2 + 1 + 71 + 572 + 4 + 4 + 4 + 8 = 666.

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

It is not an unprimeable number, because it can be changed into a prime (21715724441) 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, 3424188 + ... + 3430523.

It is an arithmetic number, because the mean of its divisors is an integer number (935668188).

Almost surely, 2^21715724448 is an apocalyptic number.

It is an amenable number.

21715724448 is an abundant number, since it is smaller than the sum of its proper divisors (45652385088).

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

21715724448 is a wasteful number, since it uses less digits than its factorization.

21715724448 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6854738 (or 6854727 counting only the distinct ones).

The product of its digits is 501760, while the sum is 45.

The spelling of 21715724448 in words is "twenty-one billion, seven hundred fifteen million, seven hundred twenty-four thousand, four hundred forty-eight".