21525332 has 24 divisors (see below), whose sum is σ = 41622336. Its totient is φ = 9688448.

The previous prime is 21525331. The next prime is 21525353. The reversal of 21525332 is 23352512.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a junction number, because it is equal to n+sod(n) for n = 21525298 and 21525307.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21525331) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 5318 + ... + 8445.

It is an arithmetic number, because the mean of its divisors is an integer number (1734264).

Almost surely, 2^21525332 is an apocalyptic number.

It is an amenable number.

21525332 is a deficient number, since it is larger than the sum of its proper divisors (20097004).

21525332 is a wasteful number, since it uses less digits than its factorization.

21525332 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13807 (or 13805 counting only the distinct ones).

The product of its digits is 1800, while the sum is 23.

The square root of 21525332 is about 4639.5400634115. The cubic root of 21525332 is about 278.1740538314.

Adding to 21525332 its reverse (23352512), we get a palindrome (44877844).

The spelling of 21525332 in words is "twenty-one million, five hundred twenty-five thousand, three hundred thirty-two".