18444915845 has 6 divisors (see below), whose sum is σ = 22134263442. Its totient is φ = 14755689728.

The previous prime is 18444915793. The next prime is 18444915847. The reversal of 18444915845 is 54851944481.

It can be written as a sum of positive squares in 3 ways, for example, as 4596568804 + 13848347041 = 67798^2 + 117679^2 .

It is not a de Polignac number, because 18444915845 - 2¹⁸ = 18444653701 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 (18444915847) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 273317 + ... + 334053.

It is an arithmetic number, because the mean of its divisors is an integer number (3689043907).

Almost surely, 2^18444915845 is an apocalyptic number.

It is an amenable number.

18444915845 is a deficient number, since it is larger than the sum of its proper divisors (3689347597).

18444915845 is an frugal number, since it uses more digits than its factorization.

18444915845 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 121479 (or 60742 counting only the distinct ones).

The product of its digits is 3686400, while the sum is 53.

The spelling of 18444915845 in words is "eighteen billion, four hundred forty-four million, nine hundred fifteen thousand, eight hundred forty-five".