205312543 has 4 divisors (see below), whose sum is σ = 210320208. Its totient is φ = 200304880.

The previous prime is 205312517. The next prime is 205312571. The reversal of 205312543 is 345213502.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-205312543 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 (205315543) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2503771 + ... + 2503852.

It is an arithmetic number, because the mean of its divisors is an integer number (52580052).

Almost surely, 2^205312543 is an apocalyptic number.

205312543 is a deficient number, since it is larger than the sum of its proper divisors (5007665).

205312543 is an equidigital number, since it uses as much as digits as its factorization.

205312543 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5007664.

The product of its (nonzero) digits is 3600, while the sum is 25.

The square root of 205312543 is about 14328.7313813889. The cubic root of 205312543 is about 589.9363552912.

The spelling of 205312543 in words is "two hundred five million, three hundred twelve thousand, five hundred forty-three".