81885344 has 12 divisors (see below), whose sum is σ = 161211834. Its totient is φ = 40942656.

The previous prime is 81885253. The next prime is 81885347. The reversal of 81885344 is 44358818.

It can be written as a sum of positive squares in only one way, i.e., 43296400 + 38588944 = 6580^2 + 6212^2 .

It is not an unprimeable number, because it can be changed into a prime (81885347) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1279427 + ... + 1279490.

Almost surely, 2^81885344 is an apocalyptic number.

It is an amenable number.

81885344 is a deficient number, since it is larger than the sum of its proper divisors (79326490).

81885344 is a wasteful number, since it uses less digits than its factorization.

81885344 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2558927 (or 2558919 counting only the distinct ones).

The product of its digits is 122880, while the sum is 41.

The square root of 81885344 is about 9049.0521050550. The cubic root of 81885344 is about 434.2455659693.

The spelling of 81885344 in words is "eighty-one million, eight hundred eighty-five thousand, three hundred forty-four".