636221636 has 12 divisors (see below), whose sum is σ = 1139280912. Its totient is φ = 310712808.

The previous prime is 636221629. The next prime is 636221671. The reversal of 636221636 is 636122636.

It is a super-2 number, since 2×636221636² = 809555940229032992, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 636221596 and 636221605.

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 3 ways as a sum of consecutive naturals, for example, 1849310 + ... + 1849653.

It is an arithmetic number, because the mean of its divisors is an integer number (94940076).

Almost surely, 2^636221636 is an apocalyptic number.

It is an amenable number.

636221636 is a deficient number, since it is larger than the sum of its proper divisors (503059276).

636221636 is a wasteful number, since it uses less digits than its factorization.

636221636 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3699010 (or 3699008 counting only the distinct ones).

The product of its digits is 46656, while the sum is 35.

The square root of 636221636 is about 25223.4342626059. The cubic root of 636221636 is about 860.0746446837.

The spelling of 636221636 in words is "six hundred thirty-six million, two hundred twenty-one thousand, six hundred thirty-six".