18805239 has 12 divisors (see below), whose sum is σ = 27508000. Its totient is φ = 12377664.

The previous prime is 18805229. The next prime is 18805243. The reversal of 18805239 is 93250881.

It is not a de Polignac number, because 18805239 - 2⁴ = 18805223 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 (18805229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 12514 + ... + 13935.

Almost surely, 2^18805239 is an apocalyptic number.

18805239 is a deficient number, since it is larger than the sum of its proper divisors (8702761).

18805239 is a wasteful number, since it uses less digits than its factorization.

18805239 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26534 (or 26531 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 36.

The square root of 18805239 is about 4336.5007782773. The cubic root of 18805239 is about 265.9252762766.

It can be divided in two parts, 18805 and 239, that added together give a square (19044 = 138²).

The spelling of 18805239 in words is "eighteen million, eight hundred five thousand, two hundred thirty-nine".