206042609 has 2 divisors, whose sum is σ = 206042610. Its totient is φ = 206042608.

The previous prime is 206042597. The next prime is 206042623. The reversal of 206042609 is 906240602.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 204404209 + 1638400 = 14297^2 + 1280^2 .

It is a cyclic number.

It is not a de Polignac number, because 206042609 - 2²⁰ = 204994033 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (206042009) 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 as a sum of consecutive naturals, namely, 103021304 + 103021305.

It is an arithmetic number, because the mean of its divisors is an integer number (103021305).

Almost surely, 2^206042609 is an apocalyptic number.

It is an amenable number.

206042609 is a deficient number, since it is larger than the sum of its proper divisors (1).

206042609 is an equidigital number, since it uses as much as digits as its factorization.

206042609 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5184, while the sum is 29.

The square root of 206042609 is about 14354.1843725096. The cubic root of 206042609 is about 590.6347750088.

The spelling of 206042609 in words is "two hundred six million, forty-two thousand, six hundred nine".