206390069 has 2 divisors, whose sum is σ = 206390070. Its totient is φ = 206390068.

The previous prime is 206390059. The next prime is 206390087. The reversal of 206390069 is 960093602.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 149206225 + 57183844 = 12215^2 + 7562^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-206390069 is a prime.

It is a super-2 number, since 2×206390069² = 85193721163649522, which contains 22 as substring.

It is a Sophie Germain prime.

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 (206390029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 103195034 + 103195035.

It is an arithmetic number, because the mean of its divisors is an integer number (103195035).

Almost surely, 2^206390069 is an apocalyptic number.

It is an amenable number.

206390069 is a deficient number, since it is larger than the sum of its proper divisors (1).

206390069 is an equidigital number, since it uses as much as digits as its factorization.

206390069 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 17496, while the sum is 35.

The square root of 206390069 is about 14366.2823653164. The cubic root of 206390069 is about 590.9665942526.

The spelling of 206390069 in words is "two hundred six million, three hundred ninety thousand, sixty-nine".