206664065 has 4 divisors (see below), whose sum is σ = 247996884. Its totient is φ = 165331248.

The previous prime is 206664061. The next prime is 206664077. The reversal of 206664065 is 560466602.

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 31181056 + 175483009 = 5584^2 + 13247^2 .

It is a cyclic number.

It is not a de Polignac number, because 206664065 - 2² = 206664061 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (206664061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20666402 + ... + 20666411.

It is an arithmetic number, because the mean of its divisors is an integer number (61999221).

Almost surely, 2^206664065 is an apocalyptic number.

It is an amenable number.

206664065 is a deficient number, since it is larger than the sum of its proper divisors (41332819).

206664065 is an equidigital number, since it uses as much as digits as its factorization.

206664065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41332818.

The product of its (nonzero) digits is 51840, while the sum is 35.

The square root of 206664065 is about 14375.8152812284. The cubic root of 206664065 is about 591.2279939127.

The spelling of 206664065 in words is "two hundred six million, six hundred sixty-four thousand, sixty-five".