21534571296 has 576 divisors, whose sum is σ = 78460462080. Its totient is φ = 5460295680.

The previous prime is 21534571283. The next prime is 21534571297. The reversal of 21534571296 is 69217543512.

21534571296 is a `hidden beast` number, since 2 + 1 + 53 + 4 + 571 + 29 + 6 = 666.

It is not an unprimeable number, because it can be changed into a prime (21534571297) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 46712506 + ... + 46712966.

It is an arithmetic number, because the mean of its divisors is an integer number (136216080).

Almost surely, 2^21534571296 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21534571296, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39230231040).

21534571296 is an abundant number, since it is smaller than the sum of its proper divisors (56925890784).

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

21534571296 is a wasteful number, since it uses less digits than its factorization.

21534571296 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 577 (or 566 counting only the distinct ones).

The product of its digits is 453600, while the sum is 45.

The spelling of 21534571296 in words is "twenty-one billion, five hundred thirty-four million, five hundred seventy-one thousand, two hundred ninety-six".