204121407 has 24 divisors (see below), whose sum is σ = 317193600. Its totient is φ = 116420976.

The previous prime is 204121373. The next prime is 204121417. The reversal of 204121407 is 704121402.

It is a happy number.

It is not a de Polignac number, because 204121407 - 2¹⁰ = 204120383 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (204121417) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 107694 + ... + 109572.

It is an arithmetic number, because the mean of its divisors is an integer number (13216400).

Almost surely, 2^204121407 is an apocalyptic number.

204121407 is a deficient number, since it is larger than the sum of its proper divisors (113072193).

204121407 is a wasteful number, since it uses less digits than its factorization.

204121407 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2635 (or 2628 counting only the distinct ones).

The product of its (nonzero) digits is 448, while the sum is 21.

The square root of 204121407 is about 14287.1063200356. The cubic root of 204121407 is about 588.7932886793.

Adding to 204121407 its reverse (704121402), we get a palindrome (908242809).

The spelling of 204121407 in words is "two hundred four million, one hundred twenty-one thousand, four hundred seven".