636843 has 4 divisors (see below), whose sum is σ = 849128. Its totient is φ = 424560.

The previous prime is 636829. The next prime is 636851. The reversal of 636843 is 348636.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 636843 - 2⁹ = 636331 is a prime.

It is a D-number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 636843.

It is not an unprimeable number, because it can be changed into a prime (636863) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 106138 + ... + 106143.

It is an arithmetic number, because the mean of its divisors is an integer number (212282).

2⁶³⁶⁸⁴³ is an apocalyptic number.

636843 is a deficient number, since it is larger than the sum of its proper divisors (212285).

636843 is a wasteful number, since it uses less digits than its factorization.

636843 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 212284.

The product of its digits is 10368, while the sum is 30.

The square root of 636843 is about 798.0244357161. The cubic root of 636843 is about 86.0354550043.

The spelling of 636843 in words is "six hundred thirty-six thousand, eight hundred forty-three".