81368844 has 24 divisors (see below), whose sum is σ = 193901568. Its totient is φ = 26545680.

The previous prime is 81368843. The next prime is 81368869. The reversal of 81368844 is 44886318.

It is a junction number, because it is equal to n+sod(n) for n = 81368796 and 81368805.

It is not an unprimeable number, because it can be changed into a prime (81368843) 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, 71572 + ... + 72699.

It is an arithmetic number, because the mean of its divisors is an integer number (8079232).

Almost surely, 2^81368844 is an apocalyptic number.

It is an amenable number.

81368844 is an abundant number, since it is smaller than the sum of its proper divisors (112532724).

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

81368844 is a wasteful number, since it uses less digits than its factorization.

81368844 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 144325 (or 144323 counting only the distinct ones).

The product of its digits is 147456, while the sum is 42.

The square root of 81368844 is about 9020.4680588094. The cubic root of 81368844 is about 433.3306237832.

The spelling of 81368844 in words is "eighty-one million, three hundred sixty-eight thousand, eight hundred forty-four".