636396646566 has 16 divisors (see below), whose sum is σ = 1288904601600. Its totient is φ = 209446997448.

The previous prime is 636396646493. The next prime is 636396646607. The reversal of 636396646566 is 665646693636.

It is a happy number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 636396646497 and 636396646506.

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, 671304006 + ... + 671304953.

It is an arithmetic number, because the mean of its divisors is an integer number (80556537600).

Almost surely, 2^636396646566 is an apocalyptic number.

636396646566 is an abundant number, since it is smaller than the sum of its proper divisors (652507955034).

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

636396646566 is a wasteful number, since it uses less digits than its factorization.

636396646566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1342609043.

The product of its digits is 453496320, while the sum is 66.

The spelling of 636396646566 in words is "six hundred thirty-six billion, three hundred ninety-six million, six hundred forty-six thousand, five hundred sixty-six".