205440517 has 4 divisors (see below), whose sum is σ = 205563276. Its totient is φ = 205317760.

The previous prime is 205440511. The next prime is 205440523. The reversal of 205440517 is 715044502.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (205440511) and next prime (205440523).

It can be written as a sum of positive squares in 2 ways, for example, as 178462881 + 26977636 = 13359^2 + 5194^2 .

It is a cyclic number.

It is not a de Polignac number, because 205440517 - 2³ = 205440509 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205440511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 58834 + ... + 62227.

It is an arithmetic number, because the mean of its divisors is an integer number (51390819).

Almost surely, 2^205440517 is an apocalyptic number.

It is an amenable number.

205440517 is a deficient number, since it is larger than the sum of its proper divisors (122759).

205440517 is a wasteful number, since it uses less digits than its factorization.

205440517 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122758.

The product of its (nonzero) digits is 5600, while the sum is 28.

The square root of 205440517 is about 14333.1963288026. The cubic root of 205440517 is about 590.0589015216.

The spelling of 205440517 in words is "two hundred five million, four hundred forty thousand, five hundred seventeen".