206228909 has 2 divisors, whose sum is σ = 206228910. Its totient is φ = 206228908.

The previous prime is 206228899. The next prime is 206228917. The reversal of 206228909 is 909822602.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 165842884 + 40386025 = 12878^2 + 6355^2 .

It is a cyclic number.

It is not a de Polignac number, because 206228909 - 2⁸ = 206228653 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (206228959) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 103114454 + 103114455.

It is an arithmetic number, because the mean of its divisors is an integer number (103114455).

Almost surely, 2^206228909 is an apocalyptic number.

It is an amenable number.

206228909 is a deficient number, since it is larger than the sum of its proper divisors (1).

206228909 is an equidigital number, since it uses as much as digits as its factorization.

206228909 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 31104, while the sum is 38.

The square root of 206228909 is about 14360.6723032036. The cubic root of 206228909 is about 590.8127351433.

The spelling of 206228909 in words is "two hundred six million, two hundred twenty-eight thousand, nine hundred nine".