8921581344 has 288 divisors, whose sum is σ = 28531077120. Its totient is φ = 2625509376.

The previous prime is 8921581327. The next prime is 8921581349. The reversal of 8921581344 is 4431851298.

8921581344 is a `hidden beast` number, since 8 + 9 + 21 + 581 + 3 + 44 = 666.

It is a tau number, because it is divible by the number of its divisors (288).

It is a super-2 number, since 2×8921581344² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 8921581344.

It is not an unprimeable number, because it can be changed into a prime (8921581349) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 13788829 + ... + 13789475.

It is an arithmetic number, because the mean of its divisors is an integer number (99066240).

Almost surely, 2^8921581344 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 8921581344, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14265538560).

8921581344 is an abundant number, since it is smaller than the sum of its proper divisors (19609495776).

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

8921581344 is a wasteful number, since it uses less digits than its factorization.

8921581344 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 832 (or 821 counting only the distinct ones).

The product of its digits is 276480, while the sum is 45.

The square root of 8921581344 is about 94454.1229592441. The cubic root of 8921581344 is about 2074.0248066920.

The spelling of 8921581344 in words is "eight billion, nine hundred twenty-one million, five hundred eighty-one thousand, three hundred forty-four".