206804109 has 16 divisors (see below), whose sum is σ = 291676032. Its totient is φ = 130065408.

The previous prime is 206804107. The next prime is 206804111. The reversal of 206804109 is 901408602.

206804109 = 1647² + 1648² + ... + 1719².

It is an interprime number because it is at equal distance from previous prime (206804107) and next prime (206804111).

It is not a de Polignac number, because 206804109 - 2¹ = 206804107 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (206804107) 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 in 15 ways as a sum of consecutive naturals, for example, 15492 + ... + 25565.

It is an arithmetic number, because the mean of its divisors is an integer number (18229752).

Almost surely, 2^206804109 is an apocalyptic number.

It is an amenable number.

206804109 is a deficient number, since it is larger than the sum of its proper divisors (84871923).

206804109 is a wasteful number, since it uses less digits than its factorization.

206804109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41156.

The product of its (nonzero) digits is 3456, while the sum is 30.

The square root of 206804109 is about 14380.6852757440. The cubic root of 206804109 is about 591.3615104932.

The spelling of 206804109 in words is "two hundred six million, eight hundred four thousand, one hundred nine".