205142305 has 4 divisors (see below), whose sum is σ = 246170772. Its totient is φ = 164113840.

The previous prime is 205142279. The next prime is 205142309. The reversal of 205142305 is 503241502.

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

It can be written as a sum of positive squares in 2 ways, for example, as 94303521 + 110838784 = 9711^2 + 10528^2 .

It is not a de Polignac number, because 205142305 - 2¹³ = 205134113 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (205142309) 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, 20514226 + ... + 20514235.

It is an arithmetic number, because the mean of its divisors is an integer number (61542693).

Almost surely, 2^205142305 is an apocalyptic number.

It is an amenable number.

205142305 is a deficient number, since it is larger than the sum of its proper divisors (41028467).

205142305 is an equidigital number, since it uses as much as digits as its factorization.

205142305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41028466.

The product of its (nonzero) digits is 1200, while the sum is 22.

The square root of 205142305 is about 14322.7897073161. The cubic root of 205142305 is about 589.7732586547.

Adding to 205142305 its reverse (503241502), we get a palindrome (708383807).

The spelling of 205142305 in words is "two hundred five million, one hundred forty-two thousand, three hundred five".