21606168 has 32 divisors (see below), whose sum is σ = 54578160. Its totient is φ = 7127040.

The previous prime is 21606161. The next prime is 21606191. The reversal of 21606168 is 86160612.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21606161) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2313 + ... + 6968.

Almost surely, 2^21606168 is an apocalyptic number.

It is an amenable number.

21606168 is an abundant number, since it is smaller than the sum of its proper divisors (32971992).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21606168 is a wasteful number, since it uses less digits than its factorization.

21606168 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9387 (or 9383 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 30.

The square root of 21606168 is about 4648.2435392307. The cubic root of 21606168 is about 278.5218361235.

The spelling of 21606168 in words is "twenty-one million, six hundred six thousand, one hundred sixty-eight".