206660005 has 8 divisors (see below), whose sum is σ = 248888952. Its totient is φ = 164730048.

The previous prime is 206659951. The next prime is 206660033. The reversal of 206660005 is 500066602.

It can be written as a sum of positive squares in 4 ways, for example, as 191844 + 206468161 = 438^2 + 14369^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 206660005 - 2⁹ = 206659493 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 73222 + ... + 75991.

It is an arithmetic number, because the mean of its divisors is an integer number (31111119).

Almost surely, 2^206660005 is an apocalyptic number.

It is an amenable number.

206660005 is a deficient number, since it is larger than the sum of its proper divisors (42228947).

206660005 is a wasteful number, since it uses less digits than its factorization.

206660005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 149495.

The product of its (nonzero) digits is 2160, while the sum is 25.

The square root of 206660005 is about 14375.6740711523. The cubic root of 206660005 is about 591.2241222488.

The spelling of 206660005 in words is "two hundred six million, six hundred sixty thousand, five".