81116439336 has 128 divisors (see below), whose sum is σ = 234019584000. Its totient is φ = 26014792896.

The previous prime is 81116439329. The next prime is 81116439337. The reversal of 81116439336 is 63393461118.

It is a happy number.

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

It is a junction number, because it is equal to n+sod(n) for n = 81116439291 and 81116439300.

It is not an unprimeable number, because it can be changed into a prime (81116439337) 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 31 ways as a sum of consecutive naturals, for example, 531255 + ... + 666681.

It is an arithmetic number, because the mean of its divisors is an integer number (1828278000).

Almost surely, 2^81116439336 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 81116439336, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (117009792000).

81116439336 is an abundant number, since it is smaller than the sum of its proper divisors (152903144664).

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

81116439336 is a wasteful number, since it uses less digits than its factorization.

81116439336 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 135548 (or 135538 counting only the distinct ones).

The product of its digits is 279936, while the sum is 45.

The spelling of 81116439336 in words is "eighty-one billion, one hundred sixteen million, four hundred thirty-nine thousand, three hundred thirty-six".