204395309161 has 4 divisors (see below), whose sum is σ = 211443423300. Its totient is φ = 197347195024.

The previous prime is 204395309149. The next prime is 204395309227. The reversal of 204395309161 is 161903593402.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 170522747136 + 33872562025 = 412944^2 + 184045^2 .

It is a cyclic number.

It is not a de Polignac number, because 204395309161 - 2⁷ = 204395309033 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (204395309101) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3524057026 + ... + 3524057083.

It is an arithmetic number, because the mean of its divisors is an integer number (52860855825).

Almost surely, 2^204395309161 is an apocalyptic number.

It is an amenable number.

204395309161 is a deficient number, since it is larger than the sum of its proper divisors (7048114139).

204395309161 is an equidigital number, since it uses as much as digits as its factorization.

204395309161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7048114138.

The product of its (nonzero) digits is 174960, while the sum is 43.

The spelling of 204395309161 in words is "two hundred four billion, three hundred ninety-five million, three hundred nine thousand, one hundred sixty-one".