204212421 has 20 divisors (see below), whose sum is σ = 348638752. Its totient is φ = 116692488.

The previous prime is 204212419. The next prime is 204212441. The reversal of 204212421 is 124212402.

204212421 is a `hidden beast` number, since 2 + 0 + 421 + 242 + 1 = 666.

It is not a de Polignac number, because 204212421 - 2¹ = 204212419 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 204212394 and 204212403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (204212441) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 179515 + ... + 180648.

Almost surely, 2^204212421 is an apocalyptic number.

204212421 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

204212421 is a deficient number, since it is larger than the sum of its proper divisors (144426331).

204212421 is an equidigital number, since it uses as much as digits as its factorization.

204212421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 360182 (or 360173 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

The square root of 204212421 is about 14290.2911446898. The cubic root of 204212421 is about 588.8807863935.

Adding to 204212421 its reverse (124212402), we get a palindrome (328424823).

The spelling of 204212421 in words is "two hundred four million, two hundred twelve thousand, four hundred twenty-one".