204442181 has 4 divisors (see below), whose sum is σ = 204509100. Its totient is φ = 204375264.

The previous prime is 204442159. The next prime is 204442207. The reversal of 204442181 is 181244402.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 181244402 = 2 ⋅90622201.

It can be written as a sum of positive squares in 2 ways, for example, as 60202081 + 144240100 = 7759^2 + 12010^2 .

It is a cyclic number.

It is not a de Polignac number, because 204442181 - 2²² = 200247877 is a prime.

It is a super-2 number, since 2×204442181² = 83593210744073522, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 204442181.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (204442981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28646 + ... + 35063.

It is an arithmetic number, because the mean of its divisors is an integer number (51127275).

Almost surely, 2^204442181 is an apocalyptic number.

It is an amenable number.

204442181 is a deficient number, since it is larger than the sum of its proper divisors (66919).

204442181 is an equidigital number, since it uses as much as digits as its factorization.

204442181 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66918.

The product of its (nonzero) digits is 2048, while the sum is 26.

The square root of 204442181 is about 14298.3279092347. The cubic root of 204442181 is about 589.1015541247.

Adding to 204442181 its reverse (181244402), we get a palindrome (385686583).

The spelling of 204442181 in words is "two hundred four million, four hundred forty-two thousand, one hundred eighty-one".