21232528 has 20 divisors (see below), whose sum is σ = 41438320. Its totient is φ = 10538784.

The previous prime is 21232513. The next prime is 21232531. The reversal of 21232528 is 82523212.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2550 + ... + 6997.

It is an arithmetic number, because the mean of its divisors is an integer number (2071916).

Almost surely, 2^21232528 is an apocalyptic number.

It is an amenable number.

21232528 is a deficient number, since it is larger than the sum of its proper divisors (20205792).

21232528 is a wasteful number, since it uses less digits than its factorization.

21232528 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9694 (or 9688 counting only the distinct ones).

The product of its digits is 1920, while the sum is 25.

The square root of 21232528 is about 4607.8767344624. The cubic root of 21232528 is about 276.9069791529.

The spelling of 21232528 in words is "twenty-one million, two hundred thirty-two thousand, five hundred twenty-eight".