206609 has 8 divisors (see below), whose sum is σ = 232512. Its totient is φ = 182160.

The previous prime is 206603. The next prime is 206623. The reversal of 206609 is 906602.

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

It is not a de Polignac number, because 206609 - 2⁴ = 206593 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (206603) 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, 47 + ... + 644.

It is an arithmetic number, because the mean of its divisors is an integer number (29064).

2²⁰⁶⁶⁰⁹ is an apocalyptic number.

It is an amenable number.

206609 is a deficient number, since it is larger than the sum of its proper divisors (25903).

206609 is a wasteful number, since it uses less digits than its factorization.

206609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 727.

The product of its (nonzero) digits is 648, while the sum is 23.

The square root of 206609 is about 454.5426272639. The cubic root of 206609 is about 59.1175478959.

The spelling of 206609 in words is "two hundred six thousand, six hundred nine".