118309 has 4 divisors (see below), whose sum is σ = 119116. Its totient is φ = 117504.

The previous prime is 118297. The next prime is 118343. The reversal of 118309 is 903811.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 903811 = 19 ⋅47569.

It can be written as a sum of positive squares in 2 ways, for example, as 9409 + 108900 = 97^2 + 330^2 .

It is a cyclic number.

It is not a de Polignac number, because 118309 - 2⁵ = 118277 is a prime.

It is a super-3 number, since 3×118309³ = 4967920133332887, which contains 333 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 118309.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (118369) 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, 114 + ... + 499.

It is an arithmetic number, because the mean of its divisors is an integer number (29779).

2¹¹⁸³⁰⁹ is an apocalyptic number.

It is an amenable number.

118309 is a deficient number, since it is larger than the sum of its proper divisors (807).

118309 is an equidigital number, since it uses as much as digits as its factorization.

118309 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 806.

The product of its (nonzero) digits is 216, while the sum is 22.

The square root of 118309 is about 343.9607535752. The cubic root of 118309 is about 49.0914576777.

The spelling of 118309 in words is "one hundred eighteen thousand, three hundred nine".