21166112 has 48 divisors (see below), whose sum is σ = 45868032. Its totient is φ = 9534720.

The previous prime is 21166111. The next prime is 21166129.

21166112 is nontrivially palindromic in base 10.

It is not an unprimeable number, because it can be changed into a prime (21166111) 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, 55073 + ... + 55455.

It is an arithmetic number, because the mean of its divisors is an integer number (955584).

Almost surely, 2^21166112 is an apocalyptic number.

21166112 is a gapful number since it is divisible by the number (22) 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 21166112, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22934016).

21166112 is an abundant number, since it is smaller than the sum of its proper divisors (24701920).

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

21166112 is a wasteful number, since it uses less digits than its factorization.

21166112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 561 (or 553 counting only the distinct ones).

The product of its digits is 144, while the sum is 20.

The square root of 21166112 is about 4600.6642998593. The cubic root of 21166112 is about 276.6179530691.

It can be divided in two parts, 2116 and 6112, that added together give a palindrome (8228).

The spelling of 21166112 in words is "twenty-one million, one hundred sixty-six thousand, one hundred twelve".