18169444661 has 4 divisors (see below), whose sum is σ = 18187929312. Its totient is φ = 18150960012.

The previous prime is 18169444639. The next prime is 18169444669. The reversal of 18169444661 is 16644496181.

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 a cyclic number.

It is not a de Polignac number, because 18169444661 - 2¹⁰ = 18169443637 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18169444669) 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, 9240851 + ... + 9242816.

It is an arithmetic number, because the mean of its divisors is an integer number (4546982328).

Almost surely, 2^18169444661 is an apocalyptic number.

It is an amenable number.

18169444661 is a deficient number, since it is larger than the sum of its proper divisors (18484651).

18169444661 is an equidigital number, since it uses as much as digits as its factorization.

18169444661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18484650.

The product of its digits is 995328, while the sum is 50.

The spelling of 18169444661 in words is "eighteen billion, one hundred sixty-nine million, four hundred forty-four thousand, six hundred sixty-one".