21108000 has 96 divisors (see below), whose sum is σ = 69189120. Its totient is φ = 5625600.

The previous prime is 21107987. The next prime is 21108007. The reversal of 21108000 is 80112.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (12).

It is not an unprimeable number, because it can be changed into a prime (21108007) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11121 + ... + 12879.

It is an arithmetic number, because the mean of its divisors is an integer number (720720).

Almost surely, 2^21108000 is an apocalyptic number.

21108000 is a gapful number since it is divisible by the number (20) 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 21108000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34594560).

21108000 is an abundant number, since it is smaller than the sum of its proper divisors (48081120).

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

21108000 is a wasteful number, since it uses less digits than its factorization.

21108000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1787 (or 1769 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

The square root of 21108000 is about 4594.3443493060. The cubic root of 21108000 is about 276.3645675911.

Adding to 21108000 its reverse (80112), we get a palindrome (21188112).

The spelling of 21108000 in words is "twenty-one million, one hundred eight thousand".