205440305 has 16 divisors (see below), whose sum is σ = 282372480. Its totient is φ = 140560512.

The previous prime is 205440281. The next prime is 205440307. The reversal of 205440305 is 503044502.

205440305 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 205440305 - 2⁸ = 205440049 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (205440307) 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, 10061 + ... + 22629.

It is an arithmetic number, because the mean of its divisors is an integer number (17648280).

Almost surely, 2^205440305 is an apocalyptic number.

It is an amenable number.

205440305 is a deficient number, since it is larger than the sum of its proper divisors (76932175).

205440305 is a wasteful number, since it uses less digits than its factorization.

205440305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13048.

The product of its (nonzero) digits is 2400, while the sum is 23.

The square root of 205440305 is about 14333.1889333812. The cubic root of 205440305 is about 590.0586985552.

Adding to 205440305 its reverse (503044502), we get a palindrome (708484807).

The spelling of 205440305 in words is "two hundred five million, four hundred forty thousand, three hundred five".