204013121 has 4 divisors (see below), whose sum is σ = 219706452. Its totient is φ = 188319792.

The previous prime is 204013109. The next prime is 204013129. The reversal of 204013121 is 121310402.

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 114918400 + 89094721 = 10720^2 + 9439^2 .

It is a cyclic number.

It is not a de Polignac number, because 204013121 - 2¹⁰ = 204012097 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 204013096 and 204013105.

It is not an unprimeable number, because it can be changed into a prime (204013129) 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, 7846646 + ... + 7846671.

It is an arithmetic number, because the mean of its divisors is an integer number (54926613).

Almost surely, 2^204013121 is an apocalyptic number.

It is an amenable number.

204013121 is a deficient number, since it is larger than the sum of its proper divisors (15693331).

204013121 is a wasteful number, since it uses less digits than its factorization.

204013121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15693330.

The product of its (nonzero) digits is 48, while the sum is 14.

The square root of 204013121 is about 14283.3161765747. The cubic root of 204013121 is about 588.6891523733.

Adding to 204013121 its reverse (121310402), we get a palindrome (325323523).

The spelling of 204013121 in words is "two hundred four million, thirteen thousand, one hundred twenty-one".