205139 has 8 divisors (see below), whose sum is σ = 237168. Its totient is φ = 175360.

The previous prime is 205133. The next prime is 205141. The reversal of 205139 is 931502.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-205139 is a prime.

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 205139.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 205139.

It is not an unprimeable number, because it can be changed into a prime (205133) 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, 362 + ... + 735.

It is an arithmetic number, because the mean of its divisors is an integer number (29646).

2²⁰⁵¹³⁹ is an apocalyptic number.

205139 is a deficient number, since it is larger than the sum of its proper divisors (32029).

205139 is a wasteful number, since it uses less digits than its factorization.

205139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1125.

The product of its (nonzero) digits is 270, while the sum is 20.

The square root of 205139 is about 452.9227307168. The cubic root of 205139 is about 58.9770091404.

The spelling of 205139 in words is "two hundred five thousand, one hundred thirty-nine".