81065244 has 72 divisors (see below), whose sum is σ = 208075392. Its totient is φ = 24548160.

The previous prime is 81065239. The next prime is 81065251. The reversal of 81065244 is 44256018.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 143707 + ... + 144269.

It is an arithmetic number, because the mean of its divisors is an integer number (2889936).

Almost surely, 2^81065244 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 81065244, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (104037696).

81065244 is an abundant number, since it is smaller than the sum of its proper divisors (127010148).

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

81065244 is a wasteful number, since it uses less digits than its factorization.

81065244 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 667 (or 652 counting only the distinct ones).

The product of its (nonzero) digits is 7680, while the sum is 30.

The square root of 81065244 is about 9003.6239370600. The cubic root of 81065244 is about 432.7910104472.

The spelling of 81065244 in words is "eighty-one million, sixty-five thousand, two hundred forty-four".