206645623137 has 6 divisors (see below), whose sum is σ = 298488122322. Its totient is φ = 137763748752.

The previous prime is 206645623123. The next prime is 206645623141. The reversal of 206645623137 is 731326546602.

206645623137 is a `hidden beast` number, since 2 + 0 + 6 + 6 + 4 + 5 + 623 + 13 + 7 = 666.

It can be written as a sum of positive squares in only one way, i.e., 189964350801 + 16681272336 = 435849^2 + 129156^2 .

It is not a de Polignac number, because 206645623137 - 2²⁴ = 206628845921 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 206645623092 and 206645623101.

It is not an unprimeable number, because it can be changed into a prime (206645623637) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 11480312388 + ... + 11480312405.

It is an arithmetic number, because the mean of its divisors is an integer number (49748020387).

Almost surely, 2^206645623137 is an apocalyptic number.

It is an amenable number.

206645623137 is a deficient number, since it is larger than the sum of its proper divisors (91842499185).

206645623137 is a wasteful number, since it uses less digits than its factorization.

206645623137 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22960624799 (or 22960624796 counting only the distinct ones).

The product of its (nonzero) digits is 1088640, while the sum is 45.

The spelling of 206645623137 in words is "two hundred six billion, six hundred forty-five million, six hundred twenty-three thousand, one hundred thirty-seven".