21836163 has 4 divisors (see below), whose sum is σ = 29114888. Its totient is φ = 14557440.

The previous prime is 21836161. The next prime is 21836167. The reversal of 21836163 is 36163812.

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

It is not a de Polignac number, because 21836163 - 2¹ = 21836161 is a prime.

It is an alternating number because its digits alternate between even and odd.

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 21836163.

It is not an unprimeable number, because it can be changed into a prime (21836161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3639358 + ... + 3639363.

It is an arithmetic number, because the mean of its divisors is an integer number (7278722).

Almost surely, 2^21836163 is an apocalyptic number.

21836163 is a deficient number, since it is larger than the sum of its proper divisors (7278725).

21836163 is an equidigital number, since it uses as much as digits as its factorization.

21836163 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7278724.

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

The square root of 21836163 is about 4672.9180390844. The cubic root of 21836163 is about 279.5066269125.

Adding to 21836163 its reverse (36163812), we get a palindrome (57999975).

The spelling of 21836163 in words is "twenty-one million, eight hundred thirty-six thousand, one hundred sixty-three".