81539231180800 has 576 divisors, whose sum is σ = 217446182553600. Its totient is φ = 30232490803200.

The previous prime is 81539231180783. The next prime is 81539231180801. The reversal of 81539231180800 is 808113293518.

It is not an unprimeable number, because it can be changed into a prime (81539231180801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 9018824280 + ... + 9018833320.

It is an arithmetic number, because the mean of its divisors is an integer number (377510733600).

Almost surely, 2^{81539231180800} is an apocalyptic number.

81539231180800 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81539231180800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (108723091276800).

81539231180800 is an abundant number, since it is smaller than the sum of its proper divisors (135906951372800).

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

81539231180800 is a wasteful number, since it uses less digits than its factorization.

81539231180800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9292 (or 9267 counting only the distinct ones).

The product of its (nonzero) digits is 414720, while the sum is 49.

The spelling of 81539231180800 in words is "eighty-one trillion, five hundred thirty-nine billion, two hundred thirty-one million, one hundred eighty thousand, eight hundred".