21184317 has 54 divisors (see below), whose sum is σ = 39224094. Its totient is φ = 10977120.

The previous prime is 21184301. The next prime is 21184327. The reversal of 21184317 is 71348112.

It can be written as a sum of positive squares in only one way, i.e., 19263321 + 1920996 = 4389^2 + 1386^2 .

It is not a de Polignac number, because 21184317 - 2⁴ = 21184301 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21184327) by changing a digit.

It is a polite number, since it can be written in 53 ways as a sum of consecutive naturals, for example, 53163 + ... + 53559.

Almost surely, 2^21184317 is an apocalyptic number.

It is an amenable number.

21184317 is a deficient number, since it is larger than the sum of its proper divisors (18039777).

21184317 is a wasteful number, since it uses less digits than its factorization.

21184317 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 439 (or 418 counting only the distinct ones).

The product of its digits is 1344, while the sum is 27.

The square root of 21184317 is about 4602.6423932346. The cubic root of 21184317 is about 276.6972368278.

The spelling of 21184317 in words is "twenty-one million, one hundred eighty-four thousand, three hundred seventeen".