18158309 has 16 divisors (see below), whose sum is σ = 20224512. Its totient is φ = 16197888.

The previous prime is 18158237. The next prime is 18158317. The reversal of 18158309 is 90385181.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18158309 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 (18158359) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 68912 + ... + 69174.

It is an arithmetic number, because the mean of its divisors is an integer number (1264032).

Almost surely, 2^18158309 is an apocalyptic number.

It is an amenable number.

18158309 is a deficient number, since it is larger than the sum of its proper divisors (2066203).

18158309 is a wasteful number, since it uses less digits than its factorization.

18158309 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 436.

The product of its (nonzero) digits is 8640, while the sum is 35.

The square root of 18158309 is about 4261.2567395077. The cubic root of 18158309 is about 262.8402071156.

The spelling of 18158309 in words is "eighteen million, one hundred fifty-eight thousand, three hundred nine".