206809247 has 2 divisors, whose sum is σ = 206809248. Its totient is φ = 206809246.

The previous prime is 206809181. The next prime is 206809249. The reversal of 206809247 is 742908602.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 206809247 - 2⁸ = 206808991 is a prime.

Together with 206809249, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 206809247.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (206809249) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 103404623 + 103404624.

It is an arithmetic number, because the mean of its divisors is an integer number (103404624).

Almost surely, 2^206809247 is an apocalyptic number.

206809247 is a deficient number, since it is larger than the sum of its proper divisors (1).

206809247 is an equidigital number, since it uses as much as digits as its factorization.

206809247 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48384, while the sum is 38.

The square root of 206809247 is about 14380.8639170253. The cubic root of 206809247 is about 591.3664078657.

The spelling of 206809247 in words is "two hundred six million, eight hundred nine thousand, two hundred forty-seven".