21122304 has 72 divisors (see below), whose sum is σ = 64263360. Its totient is φ = 6033408.

The previous prime is 21122291. The next prime is 21122323. The reversal of 21122304 is 40322112.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 3412 + ... + 7340.

Almost surely, 2^21122304 is an apocalyptic number.

21122304 is a gapful number since it is divisible by the number (24) 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 21122304, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32131680).

21122304 is an abundant number, since it is smaller than the sum of its proper divisors (43141056).

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

21122304 is an equidigital number, since it uses as much as digits as its factorization.

21122304 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3955 (or 3941 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 15.

The square root of 21122304 is about 4595.9007822189. The cubic root of 21122304 is about 276.4269803597.

Adding to 21122304 its reverse (40322112), we get a palindrome (61444416).

The spelling of 21122304 in words is "twenty-one million, one hundred twenty-two thousand, three hundred four".