206209534609 has 15 divisors (see below), whose sum is σ = 223476230237. Its totient is φ = 190276422648.

The previous prime is 206209534529. The next prime is 206209534667. The reversal of 206209534609 is 906435902602.

The square root of 206209534609 is 454103.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 2 ways, for example, as 102241981009 + 103967553600 = 319753^2 + 322440^2 .

It is not a de Polignac number, because 206209534609 - 2¹⁷ = 206209403537 is a prime.

It is not an unprimeable number, because it can be changed into a prime (206209534709) by changing a digit.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 76742064 + ... + 76744750.

Almost surely, 2^206209534609 is an apocalyptic number.

206209534609 is the 454103-rd square number.

206209534609 is the 227052-nd centered octagonal number.

It is an amenable number.

206209534609 is a deficient number, since it is larger than the sum of its proper divisors (17266695628).

206209534609 is an frugal number, since it uses more digits than its factorization.

206209534609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5426 (or 2700 counting only the distinct ones).

The product of its (nonzero) digits is 699840, while the sum is 46.

It can be divided in two parts, 2062095 and 34609, that added together give a square (2096704 = 1448²).

The spelling of 206209534609 in words is "two hundred six billion, two hundred nine million, five hundred thirty-four thousand, six hundred nine".