206135669 has 4 divisors (see below), whose sum is σ = 206166540. Its totient is φ = 206104800.

The previous prime is 206135641. The next prime is 206135681. The reversal of 206135669 is 966531602.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 58828900 + 147306769 = 7670^2 + 12137^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-206135669 is a prime.

It is a super-2 number, since 2×206135669² = 84983828068155122, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (206135609) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 782 + ... + 20319.

It is an arithmetic number, because the mean of its divisors is an integer number (51541635).

Almost surely, 2^206135669 is an apocalyptic number.

It is an amenable number.

206135669 is a deficient number, since it is larger than the sum of its proper divisors (30871).

206135669 is an equidigital number, since it uses as much as digits as its factorization.

206135669 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30870.

The product of its (nonzero) digits is 58320, while the sum is 38.

The square root of 206135669 is about 14357.4255700665. The cubic root of 206135669 is about 590.7236825079.

The spelling of 206135669 in words is "two hundred six million, one hundred thirty-five thousand, six hundred sixty-nine".