81182231328 has 96 divisors (see below), whose sum is σ = 232870220352. Its totient is φ = 24559001600.

The previous prime is 81182231327. The next prime is 81182231371. The reversal of 81182231328 is 82313228118.

It is a tau number, because it is divible by the number of its divisors (96).

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (81182231327) 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 15 ways as a sum of consecutive naturals, for example, 561388 + ... + 691028.

It is an arithmetic number, because the mean of its divisors is an integer number (2425731462).

Almost surely, 2^81182231328 is an apocalyptic number.

81182231328 is a gapful number since it is divisible by the number (88) 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 81182231328, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (116435110176).

81182231328 is an abundant number, since it is smaller than the sum of its proper divisors (151687989024).

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

81182231328 is a wasteful number, since it uses less digits than its factorization.

81182231328 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 130258 (or 130250 counting only the distinct ones).

The product of its digits is 36864, while the sum is 39.

The spelling of 81182231328 in words is "eighty-one billion, one hundred eighty-two million, two hundred thirty-one thousand, three hundred twenty-eight".