81616896 has 168 divisors, whose sum is σ = 250463304. Its totient is φ = 26542080.

The previous prime is 81616889. The next prime is 81616897. The reversal of 81616896 is 69861618.

It is a happy number.

It is a super-2 number, since 2×81616896² = 13322635425349632, which contains 22 as substring.

It is a nude number because it is divisible by every one of its digits and also a Zuckerman number because it is divisible by the product of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81616897) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1990636 + ... + 1990676.

It is an arithmetic number, because the mean of its divisors is an integer number (1490853).

Almost surely, 2^81616896 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 81616896, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (125231652).

81616896 is an abundant number, since it is smaller than the sum of its proper divisors (168846408).

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

81616896 is an frugal number, since it uses more digits than its factorization.

81616896 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82 (or 46 counting only the distinct ones).

The product of its digits is 124416, while the sum is 45.

The square root of 81616896 is about 9034.2069934223. The cubic root of 81616896 is about 433.7705115886.

81616896 divided by its product of digits (124416) gives a palindrome (656).

The spelling of 81616896 in words is "eighty-one million, six hundred sixteen thousand, eight hundred ninety-six".