21103232 has 32 divisors (see below), whose sum is σ = 42328980. Its totient is φ = 10479616.

The previous prime is 21103217. The next prime is 21103241. The reversal of 21103232 is 23230112.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 20286016 + 817216 = 4504^2 + 904^2 .

It is a tau number, because it is divible by the number of its divisors (32).

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 21668 + ... + 22620.

Almost surely, 2^21103232 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21103232, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21164490).

21103232 is an abundant number, since it is smaller than the sum of its proper divisors (21225748).

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

21103232 is an equidigital number, since it uses as much as digits as its factorization.

21103232 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1140 (or 1128 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 14.

The square root of 21103232 is about 4593.8254211496. The cubic root of 21103232 is about 276.3437570692.

Adding to 21103232 its reverse (23230112), we get a palindrome (44333344).

The spelling of 21103232 in words is "twenty-one million, one hundred three thousand, two hundred thirty-two".