21866479 has 8 divisors (see below), whose sum is σ = 22192128. Its totient is φ = 21543480.

The previous prime is 21866477. The next prime is 21866483. The reversal of 21866479 is 97466812.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21866479 - 2¹ = 21866477 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21866477) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 20694 + ... + 21724.

It is an arithmetic number, because the mean of its divisors is an integer number (2774016).

Almost surely, 2^21866479 is an apocalyptic number.

21866479 is a deficient number, since it is larger than the sum of its proper divisors (325649).

21866479 is a wasteful number, since it uses less digits than its factorization.

21866479 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1325.

The product of its digits is 145152, while the sum is 43.

The square root of 21866479 is about 4676.1607115239. The cubic root of 21866479 is about 279.6359170957.

The spelling of 21866479 in words is "twenty-one million, eight hundred sixty-six thousand, four hundred seventy-nine".