205243394 has 16 divisors (see below), whose sum is σ = 310600440. Its totient is φ = 101713920.

The previous prime is 205243393. The next prime is 205243481. The reversal of 205243394 is 493342502.

It can be written as a sum of positive squares in 4 ways, for example, as 90003169 + 115240225 = 9487^2 + 10735^2 .

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 205243394.

It is not an unprimeable number, because it can be changed into a prime (205243391) 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, 144962 + ... + 146370.

Almost surely, 2^205243394 is an apocalyptic number.

205243394 is a deficient number, since it is larger than the sum of its proper divisors (105357046).

205243394 is a wasteful number, since it uses less digits than its factorization.

205243394 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2005.

The product of its (nonzero) digits is 25920, while the sum is 32.

The square root of 205243394 is about 14326.3182290496. The cubic root of 205243394 is about 589.8701179196.

Adding to 205243394 its reverse (493342502), we get a palindrome (698585896).

The spelling of 205243394 in words is "two hundred five million, two hundred forty-three thousand, three hundred ninety-four".