204005405 has 16 divisors (see below), whose sum is σ = 248676480. Its totient is φ = 160644288.

The previous prime is 204005387. The next prime is 204005429. The reversal of 204005405 is 504500402.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 204005405 - 2²⁶ = 136896541 is a prime.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 91079 + ... + 93291.

It is an arithmetic number, because the mean of its divisors is an integer number (15542280).

Almost surely, 2^204005405 is an apocalyptic number.

It is an amenable number.

204005405 is a deficient number, since it is larger than the sum of its proper divisors (44671075).

204005405 is a wasteful number, since it uses less digits than its factorization.

204005405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2500.

The product of its (nonzero) digits is 800, while the sum is 20.

The square root of 204005405 is about 14283.0460686788. The cubic root of 204005405 is about 588.6817306566.

Adding to 204005405 its reverse (504500402), we get a palindrome (708505807).

The spelling of 204005405 in words is "two hundred four million, five thousand, four hundred five".