21126168 has 96 divisors (see below), whose sum is σ = 66044160. Its totient is φ = 5976000.

The previous prime is 21126109. The next prime is 21126169. The reversal of 21126168 is 86162112.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21126169) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 84043 + ... + 84293.

It is an arithmetic number, because the mean of its divisors is an integer number (687960).

Almost surely, 2^21126168 is an apocalyptic number.

21126168 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21126168, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33022080).

21126168 is an abundant number, since it is smaller than the sum of its proper divisors (44917992).

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

21126168 is a wasteful number, since it uses less digits than its factorization.

21126168 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 437 (or 430 counting only the distinct ones).

The product of its digits is 1152, while the sum is 27.

The square root of 21126168 is about 4596.3211376056. The cubic root of 21126168 is about 276.4438353506.

The spelling of 21126168 in words is "twenty-one million, one hundred twenty-six thousand, one hundred sixty-eight".