206886209 has 8 divisors (see below), whose sum is σ = 219969288. Its totient is φ = 193904640.

The previous prime is 206886191. The next prime is 206886217. The reversal of 206886209 is 902688602.

It can be written as a sum of positive squares in 4 ways, for example, as 39753025 + 167133184 = 6305^2 + 12928^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 206886209 - 2¹² = 206882113 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (206886299) 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, 21152 + ... + 29345.

It is an arithmetic number, because the mean of its divisors is an integer number (27496161).

Almost surely, 2^206886209 is an apocalyptic number.

It is an amenable number.

206886209 is a deficient number, since it is larger than the sum of its proper divisors (13083079).

206886209 is a wasteful number, since it uses less digits than its factorization.

206886209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50755.

The product of its (nonzero) digits is 82944, while the sum is 41.

The square root of 206886209 is about 14383.5395157103. The cubic root of 206886209 is about 591.4397558060.

The spelling of 206886209 in words is "two hundred six million, eight hundred eighty-six thousand, two hundred nine".