205442543 has 4 divisors (see below), whose sum is σ = 208924680. Its totient is φ = 201960408.

The previous prime is 205442533. The next prime is 205442551. The reversal of 205442543 is 345244502.

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

It is a cyclic number.

It is not a de Polignac number, because 205442543 - 2⁸ = 205442287 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 (205442533) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1740980 + ... + 1741097.

It is an arithmetic number, because the mean of its divisors is an integer number (52231170).

Almost surely, 2^205442543 is an apocalyptic number.

205442543 is a deficient number, since it is larger than the sum of its proper divisors (3482137).

205442543 is an equidigital number, since it uses as much as digits as its factorization.

205442543 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3482136.

The product of its (nonzero) digits is 19200, while the sum is 29.

The square root of 205442543 is about 14333.2670037225. The cubic root of 205442543 is about 590.0608411834.

The spelling of 205442543 in words is "two hundred five million, four hundred forty-two thousand, five hundred forty-three".