81087344 has 40 divisors (see below), whose sum is σ = 170978640. Its totient is φ = 37029888.

The previous prime is 81087343. The next prime is 81087373. The reversal of 81087344 is 44378018.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81087343) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18167 + ... + 22185.

It is an arithmetic number, because the mean of its divisors is an integer number (4274466).

Almost surely, 2^81087344 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 81087344, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (85489320).

81087344 is an abundant number, since it is smaller than the sum of its proper divisors (89891296).

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

81087344 is a wasteful number, since it uses less digits than its factorization.

81087344 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4137 (or 4131 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 35.

The square root of 81087344 is about 9004.8511370261. The cubic root of 81087344 is about 432.8303360233.

The spelling of 81087344 in words is "eighty-one million, eighty-seven thousand, three hundred forty-four".