204405020 has 48 divisors (see below), whose sum is σ = 442870848. Its totient is φ = 79188480.

The previous prime is 204405001. The next prime is 204405023. The reversal of 204405020 is 20504402.

It is a self number, because there is not a number n which added to its sum of digits gives 204405020.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (204405023) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 207449 + ... + 208431.

It is an arithmetic number, because the mean of its divisors is an integer number (9226476).

Almost surely, 2^204405020 is an apocalyptic number.

204405020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 204405020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (221435424).

204405020 is an abundant number, since it is smaller than the sum of its proper divisors (238465828).

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

204405020 is a wasteful number, since it uses less digits than its factorization.

204405020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1310 (or 1308 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 17.

The square root of 204405020 is about 14297.0283625654. The cubic root of 204405020 is about 589.0658587359.

Adding to 204405020 its reverse (20504402), we get a palindrome (224909422).

It can be divided in two parts, 204 and 405020, that added together give a cube (405224 = 74³).

The spelling of 204405020 in words is "two hundred four million, four hundred five thousand, twenty".