81231268608 has 720 divisors, whose sum is σ = 289665868800. Its totient is φ = 22715126784.

The previous prime is 81231268607. The next prime is 81231268619. The reversal of 81231268608 is 80686213218.

81231268608 is a `hidden beast` number, since 8 + 1 + 2 + 31 + 2 + 6 + 8 + 608 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81231268603) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 1728324841 + ... + 1728324887.

Almost surely, 2^81231268608 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 81231268608, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (144832934400).

81231268608 is an abundant number, since it is smaller than the sum of its proper divisors (208434600192).

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

81231268608 is an frugal number, since it uses more digits than its factorization.

81231268608 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111 (or 59 counting only the distinct ones).

The product of its (nonzero) digits is 221184, while the sum is 45.

The spelling of 81231268608 in words is "eighty-one billion, two hundred thirty-one million, two hundred sixty-eight thousand, six hundred eight".