81758856 has 16 divisors (see below), whose sum is σ = 204397200. Its totient is φ = 27252944.

The previous prime is 81758821. The next prime is 81758861. The reversal of 81758856 is 65885718.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 1703286 + ... + 1703333.

It is an arithmetic number, because the mean of its divisors is an integer number (12774825).

Almost surely, 2^81758856 is an apocalyptic number.

It is an amenable number.

81758856 is an abundant number, since it is smaller than the sum of its proper divisors (122638344).

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

81758856 is a wasteful number, since it uses less digits than its factorization.

81758856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3406628 (or 3406624 counting only the distinct ones).

The product of its digits is 537600, while the sum is 48.

The square root of 81758856 is about 9042.0603846690. The cubic root of 81758856 is about 434.0218582151.

The spelling of 81758856 in words is "eighty-one million, seven hundred fifty-eight thousand, eight hundred fifty-six".