18009805717 has 4 divisors (see below), whose sum is σ = 18011279520. Its totient is φ = 18008331916.

The previous prime is 18009805711. The next prime is 18009805721. The reversal of 18009805717 is 71750890081.

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 18009805717 - 2⁷ = 18009805589 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 (18009805711) 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, 718417 + ... + 743062.

It is an arithmetic number, because the mean of its divisors is an integer number (4502819880).

Almost surely, 2^18009805717 is an apocalyptic number.

It is an amenable number.

18009805717 is a deficient number, since it is larger than the sum of its proper divisors (1473803).

18009805717 is a wasteful number, since it uses less digits than its factorization.

18009805717 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1473802.

The product of its (nonzero) digits is 141120, while the sum is 46.

The spelling of 18009805717 in words is "eighteen billion, nine million, eight hundred five thousand, seven hundred seventeen".