805018605866 has 16 divisors (see below), whose sum is σ = 1249216104456. Its totient is φ = 388772050176.

The previous prime is 805018605851. The next prime is 805018605869. The reversal of 805018605866 is 668506810508.

It can be written as a sum of positive squares in 4 ways, for example, as 783881807641 + 21136798225 = 885371^2 + 145385^2 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (805018605869) 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, 39692891 + ... + 39713166.

Almost surely, 2^805018605866 is an apocalyptic number.

805018605866 is a deficient number, since it is larger than the sum of its proper divisors (444197498590).

805018605866 is a wasteful number, since it uses less digits than its factorization.

805018605866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79406233.

The product of its (nonzero) digits is 2764800, while the sum is 53.

The spelling of 805018605866 in words is "eight hundred five billion, eighteen million, six hundred five thousand, eight hundred sixty-six".