204143421 has 4 divisors (see below), whose sum is σ = 272191232. Its totient is φ = 136095612.

The previous prime is 204143413. The next prime is 204143431. The reversal of 204143421 is 124341402.

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 not a de Polignac number, because 204143421 - 2³ = 204143413 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (204143411) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 34023901 + ... + 34023906.

It is an arithmetic number, because the mean of its divisors is an integer number (68047808).

Almost surely, 2^204143421 is an apocalyptic number.

It is an amenable number.

204143421 is a deficient number, since it is larger than the sum of its proper divisors (68047811).

204143421 is an equidigital number, since it uses as much as digits as its factorization.

204143421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68047810.

The product of its (nonzero) digits is 768, while the sum is 21.

The square root of 204143421 is about 14287.8767141938. The cubic root of 204143421 is about 588.8144545624.

Adding to 204143421 its reverse (124341402), we get a palindrome (328484823).

The spelling of 204143421 in words is "two hundred four million, one hundred forty-three thousand, four hundred twenty-one".