204310021 has 4 divisors (see below), whose sum is σ = 215063200. Its totient is φ = 193556844.

The previous prime is 204310019. The next prime is 204310027. The reversal of 204310021 is 120013402.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 204310021 - 2¹ = 204310019 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 204309983 and 204310010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (204310027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5376561 + ... + 5376598.

It is an arithmetic number, because the mean of its divisors is an integer number (53765800).

Almost surely, 2^204310021 is an apocalyptic number.

It is an amenable number.

204310021 is a deficient number, since it is larger than the sum of its proper divisors (10753179).

204310021 is a wasteful number, since it uses less digits than its factorization.

204310021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10753178.

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 204310021 is about 14293.7056426946. The cubic root of 204310021 is about 588.9745867780.

Adding to 204310021 its reverse (120013402), we get a palindrome (324323423).

The spelling of 204310021 in words is "two hundred four million, three hundred ten thousand, twenty-one".