205505660 has 24 divisors (see below), whose sum is σ = 431995200. Its totient is φ = 82119744.

The previous prime is 205505647. The next prime is 205505669. The reversal of 205505660 is 66505502.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205505669) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17741 + ... + 26939.

It is an arithmetic number, because the mean of its divisors is an integer number (17999800).

Almost surely, 2^205505660 is an apocalyptic number.

205505660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

205505660 is an abundant number, since it is smaller than the sum of its proper divisors (226489540).

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

205505660 is a wasteful number, since it uses less digits than its factorization.

205505660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10325 (or 10323 counting only the distinct ones).

The product of its (nonzero) digits is 9000, while the sum is 29.

The square root of 205505660 is about 14335.4686006423. The cubic root of 205505660 is about 590.1212620619.

The spelling of 205505660 in words is "two hundred five million, five hundred five thousand, six hundred sixty".