21326685 has 8 divisors (see below), whose sum is σ = 34122720. Its totient is φ = 11374224.

The previous prime is 21326663. The next prime is 21326699. The reversal of 21326685 is 58662312.

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

It is not a de Polignac number, because 21326685 - 2⁶ = 21326621 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 710875 + ... + 710904.

It is an arithmetic number, because the mean of its divisors is an integer number (4265340).

Almost surely, 2^21326685 is an apocalyptic number.

It is an amenable number.

21326685 is a deficient number, since it is larger than the sum of its proper divisors (12796035).

21326685 is a wasteful number, since it uses less digits than its factorization.

21326685 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1421787.

The product of its digits is 17280, while the sum is 33.

The square root of 21326685 is about 4618.0823942411. The cubic root of 21326685 is about 277.3156961414.

Adding to 21326685 its reverse (58662312), we get a palindrome (79988997).

The spelling of 21326685 in words is "twenty-one million, three hundred twenty-six thousand, six hundred eighty-five".