205540231 has 8 divisors (see below), whose sum is σ = 221783184. Its totient is φ = 189359040.

The previous prime is 205540207. The next prime is 205540267. The reversal of 205540231 is 132045502.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 205540231 - 2¹¹ = 205538183 is a prime.

It is a super-2 number, since 2×205540231² = 84493573119066722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205540331) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8401 + ... + 21946.

It is an arithmetic number, because the mean of its divisors is an integer number (27722898).

Almost surely, 2^205540231 is an apocalyptic number.

205540231 is a deficient number, since it is larger than the sum of its proper divisors (16242953).

205540231 is a wasteful number, since it uses less digits than its factorization.

205540231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30881.

The product of its (nonzero) digits is 1200, while the sum is 22.

The square root of 205540231 is about 14336.6743354238. The cubic root of 205540231 is about 590.1543510748.

Adding to 205540231 its reverse (132045502), we get a palindrome (337585733).

The spelling of 205540231 in words is "two hundred five million, five hundred forty thousand, two hundred thirty-one".