206018861 has 2 divisors, whose sum is σ = 206018862. Its totient is φ = 206018860.

The previous prime is 206018837. The next prime is 206018863. The reversal of 206018861 is 168810602.

206018861 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., 204661636 + 1357225 = 14306^2 + 1165^2 .

It is a cyclic number.

It is not a de Polignac number, because 206018861 - 2¹⁸ = 205756717 is a prime.

It is a Sophie Germain prime.

Together with 206018863, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (206018863) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 103009430 + 103009431.

It is an arithmetic number, because the mean of its divisors is an integer number (103009431).

Almost surely, 2^206018861 is an apocalyptic number.

It is an amenable number.

206018861 is a deficient number, since it is larger than the sum of its proper divisors (1).

206018861 is an equidigital number, since it uses as much as digits as its factorization.

206018861 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4608, while the sum is 32.

The square root of 206018861 is about 14353.3571334375. The cubic root of 206018861 is about 590.6120823990.

The spelling of 206018861 in words is "two hundred six million, eighteen thousand, eight hundred sixty-one".