204166121 has 4 divisors (see below), whose sum is σ = 204613332. Its totient is φ = 203718912.

The previous prime is 204166103. The next prime is 204166133. The reversal of 204166121 is 121661402.

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 194212096 + 9954025 = 13936^2 + 3155^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-204166121 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (204166421) 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, 222920 + ... + 223833.

It is an arithmetic number, because the mean of its divisors is an integer number (51153333).

Almost surely, 2^204166121 is an apocalyptic number.

It is an amenable number.

204166121 is a deficient number, since it is larger than the sum of its proper divisors (447211).

204166121 is an equidigital number, since it uses as much as digits as its factorization.

204166121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 447210.

The product of its (nonzero) digits is 576, while the sum is 23.

The square root of 204166121 is about 14288.6710718667. The cubic root of 204166121 is about 588.8362784230.

The spelling of 204166121 in words is "two hundred four million, one hundred sixty-six thousand, one hundred twenty-one".