209139 has 16 divisors (see below), whose sum is σ = 333312. Its totient is φ = 114048.

The previous prime is 209123. The next prime is 209147. The reversal of 209139 is 931902.

It is a happy number.

It is not a de Polignac number, because 209139 - 2⁴ = 209123 is a prime.

It is a zygodrome in base 2.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 209139.

It is not an unprimeable number, because it can be changed into a prime (209159) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 267 + ... + 699.

It is an arithmetic number, because the mean of its divisors is an integer number (20832).

2²⁰⁹¹³⁹ is an apocalyptic number.

209139 is a deficient number, since it is larger than the sum of its proper divisors (124173).

209139 is a wasteful number, since it uses less digits than its factorization.

209139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 466.

The product of its (nonzero) digits is 486, while the sum is 24.

The square root of 209139 is about 457.3171765854. The cubic root of 209139 is about 59.3578746548.

The spelling of 209139 in words is "two hundred nine thousand, one hundred thirty-nine".