81086711193856 has 81 divisors (see below), whose sum is σ = 164663770278511. Its totient is φ = 39852001843712.

The previous prime is 81086711193811. The next prime is 81086711193911. The reversal of 81086711193856 is 65839111768018.

The square root of 81086711193856 is 9004816.

It is a perfect power (a square), and thus also a powerful number.

81086711193856 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (64).

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 8500541535 + ... + 8500551073.

Almost surely, 2^{81086711193856} is an apocalyptic number.

81086711193856 is the 9004816-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81086711193856

81086711193856 is an abundant number, since it is smaller than the sum of its proper divisors (83577059084655).

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

81086711193856 is an frugal number, since it uses more digits than its factorization.

81086711193856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19212 (or 9600 counting only the distinct ones).

The product of its (nonzero) digits is 17418240, while the sum is 64.

81086711193856 divided by its sum of digits (64) gives a square (1266979862404 = 1125602²).

The spelling of 81086711193856 in words is "eighty-one trillion, eighty-six billion, seven hundred eleven million, one hundred ninety-three thousand, eight hundred fifty-six".