205043352561 has 8 divisors (see below), whose sum is σ = 303767929760. Its totient is φ = 136695568356.

The previous prime is 205043352541. The next prime is 205043352571. The reversal of 205043352561 is 165253340502.

205043352561 is a `hidden beast` number, since 2 + 0 + 5 + 0 + 43 + 3 + 52 + 561 = 666.

It is not a de Polignac number, because 205043352561 - 2⁵ = 205043352529 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (205043352541) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3797099095 + ... + 3797099148.

It is an arithmetic number, because the mean of its divisors is an integer number (37970991220).

Almost surely, 2^205043352561 is an apocalyptic number.

It is an amenable number.

205043352561 is a deficient number, since it is larger than the sum of its proper divisors (98724577199).

205043352561 is an equidigital number, since it uses as much as digits as its factorization.

205043352561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7594198252 (or 7594198246 counting only the distinct ones).

The product of its (nonzero) digits is 108000, while the sum is 36.

The spelling of 205043352561 in words is "two hundred five billion, forty-three million, three hundred fifty-two thousand, five hundred sixty-one".