204121404 has 48 divisors (see below), whose sum is σ = 534471840. Its totient is φ = 67363200.

The previous prime is 204121373. The next prime is 204121417. The reversal of 204121404 is 404121402.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 1552 + ... + 20264.

It is an arithmetic number, because the mean of its divisors is an integer number (11134830).

Almost surely, 2^204121404 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 204121404, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (267235920).

204121404 is an abundant number, since it is smaller than the sum of its proper divisors (330350436).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

204121404 is a wasteful number, since it uses less digits than its factorization.

204121404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18827 (or 18819 counting only the distinct ones).

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

The square root of 204121404 is about 14287.1062150458. The cubic root of 204121404 is about 588.7932857947.

Adding to 204121404 its reverse (404121402), we get a palindrome (608242806).

The spelling of 204121404 in words is "two hundred four million, one hundred twenty-one thousand, four hundred four".