1205116866 has 40 divisors (see below), whose sum is σ = 2793481020. Its totient is φ = 387852192.

The previous prime is 1205116849. The next prime is 1205116903. The reversal of 1205116866 is 6686115021.

1205116866 is a `hidden beast` number, since 1 + 20 + 511 + 68 + 66 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 1178892225 + 26224641 = 34335^2 + 5121^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 1205116866.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 123561 + ... + 132956.

Almost surely, 2^1205116866 is an apocalyptic number.

1205116866 is an abundant number, since it is smaller than the sum of its proper divisors (1588364154).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1205116866 is a wasteful number, since it uses less digits than its factorization.

1205116866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 256560 (or 256551 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 36.

The square root of 1205116866 is about 34714.7931867669. The cubic root of 1205116866 is about 1064.1668389563.

The spelling of 1205116866 in words is "one billion, two hundred five million, one hundred sixteen thousand, eight hundred sixty-six".