21043532 has 6 divisors (see below), whose sum is σ = 36826188. Its totient is φ = 10521764.

The previous prime is 21043523. The next prime is 21043543. The reversal of 21043532 is 23534012.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2630438 + ... + 2630445.

It is an arithmetic number, because the mean of its divisors is an integer number (6137698).

Almost surely, 2^21043532 is an apocalyptic number.

It is an amenable number.

21043532 is a deficient number, since it is larger than the sum of its proper divisors (15782656).

21043532 is a wasteful number, since it uses less digits than its factorization.

21043532 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5260887 (or 5260885 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 20.

The square root of 21043532 is about 4587.3229666114. The cubic root of 21043532 is about 276.0829233436.

Adding to 21043532 its reverse (23534012), we get a palindrome (44577544).

The spelling of 21043532 in words is "twenty-one million, forty-three thousand, five hundred thirty-two".