18006109685 has 4 divisors (see below), whose sum is σ = 21607331628. Its totient is φ = 14404887744.

The previous prime is 18006109643. The next prime is 18006109711. The reversal of 18006109685 is 58690160081.

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 9936501124 + 8069608561 = 99682^2 + 89831^2 .

It is a cyclic number.

It is not a de Polignac number, because 18006109685 - 2⁶ = 18006109621 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1800610964 + ... + 1800610973.

It is an arithmetic number, because the mean of its divisors is an integer number (5401832907).

Almost surely, 2^18006109685 is an apocalyptic number.

It is an amenable number.

18006109685 is a deficient number, since it is larger than the sum of its proper divisors (3601221943).

18006109685 is an equidigital number, since it uses as much as digits as its factorization.

18006109685 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3601221942.

The product of its (nonzero) digits is 103680, while the sum is 44.

The spelling of 18006109685 in words is "eighteen billion, six million, one hundred nine thousand, six hundred eighty-five".