206115516561 has 16 divisors (see below), whose sum is σ = 290605045248. Its totient is φ = 129734390400.

The previous prime is 206115516491. The next prime is 206115516599. The reversal of 206115516561 is 165615511602.

It is not a de Polignac number, because 206115516561 - 2⁷ = 206115516433 is a prime.

It is not an unprimeable number, because it can be changed into a prime (206115516161) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27024186 + ... + 27031811.

It is an arithmetic number, because the mean of its divisors is an integer number (18162815328).

Almost surely, 2^206115516561 is an apocalyptic number.

It is an amenable number.

206115516561 is a deficient number, since it is larger than the sum of its proper divisors (84489528687).

206115516561 is a wasteful number, since it uses less digits than its factorization.

206115516561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54056072.

The product of its (nonzero) digits is 54000, while the sum is 39.

The spelling of 206115516561 in words is "two hundred six billion, one hundred fifteen million, five hundred sixteen thousand, five hundred sixty-one".