81108736 has 36 divisors (see below), whose sum is σ = 166295752. Its totient is φ = 39453696.

The previous prime is 81108733. The next prime is 81108743. The reversal of 81108736 is 63780118.

It is a hoax number, since the sum of its digits (34) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81108733) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5191 + ... + 13753.

Almost surely, 2^81108736 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 81108736, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (83147876).

81108736 is an abundant number, since it is smaller than the sum of its proper divisors (85187016).

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

81108736 is an equidigital number, since it uses as much as digits as its factorization.

81108736 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8616 (or 8602 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 34.

The square root of 81108736 is about 9006.0388628964. The cubic root of 81108736 is about 432.8683949525.

The spelling of 81108736 in words is "eighty-one million, one hundred eight thousand, seven hundred thirty-six".