81811112 has 32 divisors (see below), whose sum is σ = 165237600. Its totient is φ = 37848384.

The previous prime is 81811109. The next prime is 81811141. The reversal of 81811112 is 21111818.

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

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 in 7 ways as a sum of consecutive naturals, for example, 278 + ... + 12794.

It is an arithmetic number, because the mean of its divisors is an integer number (5163675).

Almost surely, 2^81811112 is an apocalyptic number.

It is an amenable number.

81811112 is an abundant number, since it is smaller than the sum of its proper divisors (83426488).

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

81811112 is a wasteful number, since it uses less digits than its factorization.

81811112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12585 (or 12581 counting only the distinct ones).

The product of its digits is 128, while the sum is 23.

The square root of 81811112 is about 9044.9495299863. The cubic root of 81811112 is about 434.1143065730.

The spelling of 81811112 in words is "eighty-one million, eight hundred eleven thousand, one hundred twelve".