18723685705 has 4 divisors (see below), whose sum is σ = 22468422852. Its totient is φ = 14978948560.

The previous prime is 18723685667. The next prime is 18723685723. The reversal of 18723685705 is 50758632781.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 9134771776 + 9588913929 = 95576^2 + 97923^2 .

It is not a de Polignac number, because 18723685705 - 2²⁷ = 18589467977 is a prime.

It is a Duffinian number.

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 3 ways as a sum of consecutive naturals, for example, 1872368566 + ... + 1872368575.

It is an arithmetic number, because the mean of its divisors is an integer number (5617105713).

Almost surely, 2^18723685705 is an apocalyptic number.

It is an amenable number.

18723685705 is a deficient number, since it is larger than the sum of its proper divisors (3744737147).

18723685705 is an equidigital number, since it uses as much as digits as its factorization.

18723685705 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3744737146.

The product of its (nonzero) digits is 2822400, while the sum is 52.

The spelling of 18723685705 in words is "eighteen billion, seven hundred twenty-three million, six hundred eighty-five thousand, seven hundred five".