81046656 has 80 divisors (see below), whose sum is σ = 241224390. Its totient is φ = 27012096.

The previous prime is 81046649. The next prime is 81046673. The reversal of 81046656 is 65664018.

It can be written as a sum of positive squares in only one way, i.e., 81000000 + 46656 = 9000^2 + 216^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 81046656.

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 6460 + ... + 14276.

Almost surely, 2^81046656 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 81046656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (120612195).

81046656 is an abundant number, since it is smaller than the sum of its proper divisors (160177734).

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

81046656 is an equidigital number, since it uses as much as digits as its factorization.

81046656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7843 (or 7822 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The square root of 81046656 is about 9002.5916268595. The cubic root of 81046656 is about 432.7579287224.

The spelling of 81046656 in words is "eighty-one million, forty-six thousand, six hundred fifty-six".