81811093776 has 40 divisors (see below), whose sum is σ = 212407387200. Its totient is φ = 27133324416.

The previous prime is 81811093759. The next prime is 81811093783. The reversal of 81811093776 is 67739011818.

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 7 ways as a sum of consecutive naturals, for example, 4272855 + ... + 4291958.

It is an arithmetic number, because the mean of its divisors is an integer number (5310184680).

Almost surely, 2^81811093776 is an apocalyptic number.

It is an amenable number.

81811093776 is an abundant number, since it is smaller than the sum of its proper divisors (130596293424).

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

81811093776 is a wasteful number, since it uses less digits than its factorization.

81811093776 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8565023 (or 8565017 counting only the distinct ones).

The product of its (nonzero) digits is 508032, while the sum is 51.

The spelling of 81811093776 in words is "eighty-one billion, eight hundred eleven million, ninety-three thousand, seven hundred seventy-six".