206563664668 has 24 divisors (see below), whose sum is σ = 382830879312. Its totient is φ = 97185970944.

The previous prime is 206563664641. The next prime is 206563664689. The reversal of 206563664668 is 866466365602.

It is a super-2 number, since 2×206563664668² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8230 + ... + 642802.

It is an arithmetic number, because the mean of its divisors is an integer number (15951286638).

Almost surely, 2^206563664668 is an apocalyptic number.

It is an amenable number.

206563664668 is a deficient number, since it is larger than the sum of its proper divisors (176267214644).

206563664668 is a wasteful number, since it uses less digits than its factorization.

206563664668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 639381 (or 639379 counting only the distinct ones).

The product of its (nonzero) digits is 44789760, while the sum is 58.

The spelling of 206563664668 in words is "two hundred six billion, five hundred sixty-three million, six hundred sixty-four thousand, six hundred sixty-eight".