205440321 has 24 divisors (see below), whose sum is σ = 286719264. Its totient is φ = 130829440.

The previous prime is 205440307. The next prime is 205440329. The reversal of 205440321 is 123044502.

It is not a de Polignac number, because 205440321 - 2⁹ = 205439809 is a prime.

It is not an unprimeable number, because it can be changed into a prime (205440329) 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 23 ways as a sum of consecutive naturals, for example, 269581 + ... + 270341.

It is an arithmetic number, because the mean of its divisors is an integer number (11946636).

Almost surely, 2^205440321 is an apocalyptic number.

It is an amenable number.

205440321 is a deficient number, since it is larger than the sum of its proper divisors (81278943).

205440321 is a wasteful number, since it uses less digits than its factorization.

205440321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 929 (or 900 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 21.

The square root of 205440321 is about 14333.1894915263. The cubic root of 205440321 is about 590.0587138734.

Adding to 205440321 its reverse (123044502), we get a palindrome (328484823).

It can be divided in two parts, 205440 and 321, that added together give a triangular number (205761 = T₆₄₁).

The spelling of 205440321 in words is "two hundred five million, four hundred forty thousand, three hundred twenty-one".