205161620618 has 16 divisors (see below), whose sum is σ = 318444059880. Its totient is φ = 99015596736.

The previous prime is 205161620611. The next prime is 205161620621. The reversal of 205161620618 is 816026161502.

It is a happy number.

205161620618 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 118765012129 + 86396608489 = 344623^2 + 293933^2 .

It is not an unprimeable number, because it can be changed into a prime (205161620611) 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 7 ways as a sum of consecutive naturals, for example, 290921 + ... + 703532.

Almost surely, 2^205161620618 is an apocalyptic number.

205161620618 is a deficient number, since it is larger than the sum of its proper divisors (113282439262).

205161620618 is a wasteful number, since it uses less digits than its factorization.

205161620618 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 998041.

The product of its (nonzero) digits is 34560, while the sum is 38.

The spelling of 205161620618 in words is "two hundred five billion, one hundred sixty-one million, six hundred twenty thousand, six hundred eighteen".