636816 has 20 divisors (see below), whose sum is σ = 1645232. Its totient is φ = 212256.

The previous prime is 636809. The next prime is 636817. The reversal of 636816 is 618636.

636816 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Smith number, since the sum of its digits (30) coincides with the sum of the digits of its prime factors.

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (636817) by changing a digit.

636816 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6586 + ... + 6681.

2⁶³⁶⁸¹⁶ is an apocalyptic number.

It is an amenable number.

636816 is an abundant number, since it is smaller than the sum of its proper divisors (1008416).

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

636816 is a wasteful number, since it uses less digits than its factorization.

636816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13278 (or 13272 counting only the distinct ones).

The product of its digits is 5184, while the sum is 30.

The square root of 636816 is about 798.0075187616. The cubic root of 636816 is about 86.0342391158.

The spelling of 636816 in words is "six hundred thirty-six thousand, eight hundred sixteen".