18009791 has 8 divisors (see below), whose sum is σ = 18653184. Its totient is φ = 17370360.

The previous prime is 18009763. The next prime is 18009821. The reversal of 18009791 is 19790081.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 18009791 - 2¹⁸ = 17747647 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 (18009191) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10586 + ... + 12168.

It is an arithmetic number, because the mean of its divisors is an integer number (2331648).

Almost surely, 2^18009791 is an apocalyptic number.

18009791 is a deficient number, since it is larger than the sum of its proper divisors (643393).

18009791 is a wasteful number, since it uses less digits than its factorization.

18009791 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1981.

The product of its (nonzero) digits is 4536, while the sum is 35.

The square root of 18009791 is about 4243.7944106660. The cubic root of 18009791 is about 262.1216487318.

The spelling of 18009791 in words is "eighteen million, nine thousand, seven hundred ninety-one".