206006681 has 2 divisors, whose sum is σ = 206006682. Its totient is φ = 206006680.

The previous prime is 206006659. The next prime is 206006693. The reversal of 206006681 is 186600602.

206006681 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 204032656 + 1974025 = 14284^2 + 1405^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-206006681 is a prime.

It is a super-2 number, since 2×206006681² = 84877505233271522, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (206006611) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 103003340 + 103003341.

It is an arithmetic number, because the mean of its divisors is an integer number (103003341).

Almost surely, 2^206006681 is an apocalyptic number.

It is an amenable number.

206006681 is a deficient number, since it is larger than the sum of its proper divisors (1).

206006681 is an equidigital number, since it uses as much as digits as its factorization.

206006681 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3456, while the sum is 29.

The square root of 206006681 is about 14352.9328361837. The cubic root of 206006681 is about 590.6004430166.

The spelling of 206006681 in words is "two hundred six million, six thousand, six hundred eighty-one".