206559137 has 2 divisors, whose sum is σ = 206559138. Its totient is φ = 206559136.

The previous prime is 206559109. The next prime is 206559139. The reversal of 206559137 is 731955602.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 120143521 + 86415616 = 10961^2 + 9296^2 .

It is a cyclic number.

It is not a de Polignac number, because 206559137 - 2¹⁰ = 206558113 is a prime.

Together with 206559139, 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 206559137.

It is not a weakly prime, because it can be changed into another prime (206559139) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 103279568 + 103279569.

It is an arithmetic number, because the mean of its divisors is an integer number (103279569).

Almost surely, 2^206559137 is an apocalyptic number.

It is an amenable number.

206559137 is a deficient number, since it is larger than the sum of its proper divisors (1).

206559137 is an equidigital number, since it uses as much as digits as its factorization.

206559137 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 56700, while the sum is 38.

The square root of 206559137 is about 14372.1653552970. The cubic root of 206559137 is about 591.1279170512.

It can be divided in two parts, 20655 and 9137, that added together give a palindrome (29792).

The spelling of 206559137 in words is "two hundred six million, five hundred fifty-nine thousand, one hundred thirty-seven".