206109945 has 24 divisors (see below), whose sum is σ = 357898632. Its totient is φ = 109728000.

The previous prime is 206109941. The next prime is 206109961. The reversal of 206109945 is 549901602.

It can be written as a sum of positive squares in 4 ways, for example, as 91470096 + 114639849 = 9564^2 + 10707^2 .

It is not a de Polignac number, because 206109945 - 2² = 206109941 is a prime.

It is not an unprimeable number, because it can be changed into a prime (206109941) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 23235 + ... + 30855.

It is an arithmetic number, because the mean of its divisors is an integer number (14912443).

Almost surely, 2^206109945 is an apocalyptic number.

It is an amenable number.

206109945 is a deficient number, since it is larger than the sum of its proper divisors (151788687).

206109945 is a wasteful number, since it uses less digits than its factorization.

206109945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8233 (or 8230 counting only the distinct ones).

The product of its (nonzero) digits is 19440, while the sum is 36.

The square root of 206109945 is about 14356.5296990603. The cubic root of 206109945 is about 590.6991090345.

The spelling of 206109945 in words is "two hundred six million, one hundred nine thousand, nine hundred forty-five".