206664005 has 16 divisors (see below), whose sum is σ = 258839280. Its totient is φ = 158204928.

The previous prime is 206664001. The next prime is 206664023. The reversal of 206664005 is 500466602.

It can be written as a sum of positive squares in 8 ways, for example, as 34975396 + 171688609 = 5914^2 + 13103^2 .

It is a cyclic number.

It is not a de Polignac number, because 206664005 - 2² = 206664001 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (29).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (206664001) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10079 + ... + 22691.

It is an arithmetic number, because the mean of its divisors is an integer number (16177455).

Almost surely, 2^206664005 is an apocalyptic number.

It is an amenable number.

206664005 is a deficient number, since it is larger than the sum of its proper divisors (52175275).

206664005 is a wasteful number, since it uses less digits than its factorization.

206664005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12760.

The product of its (nonzero) digits is 8640, while the sum is 29.

The square root of 206664005 is about 14375.8131943901. The cubic root of 206664005 is about 591.2279366963.

The spelling of 206664005 in words is "two hundred six million, six hundred sixty-four thousand, five".