81168107805 has 48 divisors (see below), whose sum is σ = 146007126720. Its totient is φ = 43258520448.

The previous prime is 81168107803. The next prime is 81168107831. The reversal of 81168107805 is 50870186118.

It is not a de Polignac number, because 81168107805 - 2¹ = 81168107803 is a prime.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81168107803) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1717786 + ... + 1764404.

It is an arithmetic number, because the mean of its divisors is an integer number (3041815140).

Almost surely, 2^81168107805 is an apocalyptic number.

It is an amenable number.

81168107805 is a deficient number, since it is larger than the sum of its proper divisors (64839018915).

81168107805 is a wasteful number, since it uses less digits than its factorization.

81168107805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48072 (or 48060 counting only the distinct ones).

The product of its (nonzero) digits is 107520, while the sum is 45.

The spelling of 81168107805 in words is "eighty-one billion, one hundred sixty-eight million, one hundred seven thousand, eight hundred five".