21043932 has 72 divisors (see below), whose sum is σ = 61535376. Its totient is φ = 5548032.

The previous prime is 21043927. The next prime is 21043949. The reversal of 21043932 is 23934012.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6268 + ... + 9020.

It is an arithmetic number, because the mean of its divisors is an integer number (854658).

Almost surely, 2^21043932 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 21043932, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30767688).

21043932 is an abundant number, since it is smaller than the sum of its proper divisors (40491444).

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

21043932 is a wasteful number, since it uses less digits than its factorization.

21043932 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2787 (or 2778 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 24.

The square root of 21043932 is about 4587.3665648169. The cubic root of 21043932 is about 276.0846726138.

Adding to 21043932 its reverse (23934012), we get a palindrome (44977944).

The spelling of 21043932 in words is "twenty-one million, forty-three thousand, nine hundred thirty-two".