21107200 has 120 divisors (see below), whose sum is σ = 55941732. Its totient is φ = 7864320.

The previous prime is 21107189. The next prime is 21107209. The reversal of 21107200 is 270112.

It can be written as a sum of positive squares in 6 ways, for example, as 10137856 + 10969344 = 3184^2 + 3312^2 .

It is not an unprimeable number, because it can be changed into a prime (21107209) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 217552 + ... + 217648.

Almost surely, 2^21107200 is an apocalyptic number.

21107200 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 21107200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27970866).

21107200 is an abundant number, since it is smaller than the sum of its proper divisors (34834532).

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

21107200 is an equidigital number, since it uses as much as digits as its factorization.

21107200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 142 (or 121 counting only the distinct ones).

The product of its (nonzero) digits is 28, while the sum is 13.

The square root of 21107200 is about 4594.2572849156. The cubic root of 21107200 is about 276.3610761116.

Adding to 21107200 its reverse (270112), we get a palindrome (21377312).

The spelling of 21107200 in words is "twenty-one million, one hundred seven thousand, two hundred".