81735423123 has 4 divisors (see below), whose sum is σ = 108980564168. Its totient is φ = 54490282080.

The previous prime is 81735423079. The next prime is 81735423137. The reversal of 81735423123 is 32132453718.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 81735423123 - 2⁹ = 81735422611 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81735421123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13622570518 + ... + 13622570523.

It is an arithmetic number, because the mean of its divisors is an integer number (27245141042).

Almost surely, 2^81735423123 is an apocalyptic number.

81735423123 is a deficient number, since it is larger than the sum of its proper divisors (27245141045).

81735423123 is a wasteful number, since it uses less digits than its factorization.

81735423123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27245141044.

The product of its digits is 120960, while the sum is 39.

The spelling of 81735423123 in words is "eighty-one billion, seven hundred thirty-five million, four hundred twenty-three thousand, one hundred twenty-three".