205442239 has 4 divisors (see below), whose sum is σ = 212069440. Its totient is φ = 198815040.

The previous prime is 205442213. The next prime is 205442287. The reversal of 205442239 is 932244502.

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-205442239 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (31), and also a Moran number because the ratio is a prime number: 6627169 = 205442239 / (2 + 0 + 5 + 4 + 4 + 2 + 2 + 3 + 9).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 205442239.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205442299) 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, 3313554 + ... + 3313615.

It is an arithmetic number, because the mean of its divisors is an integer number (53017360).

Almost surely, 2^205442239 is an apocalyptic number.

205442239 is a deficient number, since it is larger than the sum of its proper divisors (6627201).

205442239 is an equidigital number, since it uses as much as digits as its factorization.

205442239 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6627200.

The product of its (nonzero) digits is 17280, while the sum is 31.

The square root of 205442239 is about 14333.2563990183. The cubic root of 205442239 is about 590.0605501392.

The spelling of 205442239 in words is "two hundred five million, four hundred forty-two thousand, two hundred thirty-nine".