205405000 has 40 divisors (see below), whose sum is σ = 481275630. Its totient is φ = 82160000.

The previous prime is 205404971. The next prime is 205405001. The reversal of 205405000 is 504502.

It is a happy number.

205405000 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 5 ways, for example, as 972196 + 204432804 = 986^2 + 14298^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is not an unprimeable number, because it can be changed into a prime (205405001) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 15541 + ... + 25540.

Almost surely, 2^205405000 is an apocalyptic number.

205405000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

205405000 is an abundant number, since it is smaller than the sum of its proper divisors (275870630).

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

205405000 is an equidigital number, since it uses as much as digits as its factorization.

205405000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41107 (or 41088 counting only the distinct ones).

The product of its (nonzero) digits is 200, while the sum is 16.

The square root of 205405000 is about 14331.9572982897. The cubic root of 205405000 is about 590.0248960097.

Adding to 205405000 its reverse (504502), we get a palindrome (205909502).

The spelling of 205405000 in words is "two hundred five million, four hundred five thousand".