81398084832 has 288 divisors, whose sum is σ = 254062448640. Its totient is φ = 24624000000.

The previous prime is 81398084821. The next prime is 81398084837. The reversal of 81398084832 is 23848089318.

It is a happy number.

81398084832 is a `hidden beast` number, since 81 + 3 + 9 + 80 + 8 + 483 + 2 = 666.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81398084837) 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, 17130457 + ... + 17135207.

It is an arithmetic number, because the mean of its divisors is an integer number (882161280).

Almost surely, 2^81398084832 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 81398084832, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (127031224320).

81398084832 is an abundant number, since it is smaller than the sum of its proper divisors (172664363808).

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

81398084832 is a wasteful number, since it uses less digits than its factorization.

81398084832 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4918 (or 4907 counting only the distinct ones).

The product of its (nonzero) digits is 2654208, while the sum is 54.

The spelling of 81398084832 in words is "eighty-one billion, three hundred ninety-eight million, eighty-four thousand, eight hundred thirty-two".