81795444897 has 4 divisors (see below), whose sum is σ = 109060593200. Its totient is φ = 54530296596.

The previous prime is 81795444889. The next prime is 81795444911. The reversal of 81795444897 is 79844459718.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 81795444897 - 2³ = 81795444889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81795440897) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13632574147 + ... + 13632574152.

It is an arithmetic number, because the mean of its divisors is an integer number (27265148300).

Almost surely, 2^81795444897 is an apocalyptic number.

It is an amenable number.

81795444897 is a deficient number, since it is larger than the sum of its proper divisors (27265148303).

81795444897 is a wasteful number, since it uses less digits than its factorization.

81795444897 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27265148302.

The product of its digits is 81285120, while the sum is 66.

The spelling of 81795444897 in words is "eighty-one billion, seven hundred ninety-five million, four hundred forty-four thousand, eight hundred ninety-seven".