206123806165128 has 128 divisors (see below), whose sum is σ = 550206530496000. Its totient is φ = 64164019968000.

The previous prime is 206123806165117. The next prime is 206123806165129. The reversal of 206123806165128 is 821561608321602.

It is not an unprimeable number, because it can be changed into a prime (206123806165129) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1819243 + ... + 20385221.

It is an arithmetic number, because the mean of its divisors is an integer number (4298488519500).

Almost surely, 2^{206123806165128} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 206123806165128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (275103265248000).

206123806165128 is an abundant number, since it is smaller than the sum of its proper divisors (344082724330872).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

206123806165128 is a wasteful number, since it uses less digits than its factorization.

206123806165128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18566355 (or 18566351 counting only the distinct ones).

The product of its (nonzero) digits is 1658880, while the sum is 51.

The spelling of 206123806165128 in words is "two hundred six trillion, one hundred twenty-three billion, eight hundred six million, one hundred sixty-five thousand, one hundred twenty-eight".