21523332 has 12 divisors (see below), whose sum is σ = 50221136. Its totient is φ = 7174440.

The previous prime is 21523283. The next prime is 21523339. The reversal of 21523332 is 23332512.

It is a tau number, because it is divible by the number of its divisors (12).

It is a junction number, because it is equal to n+sod(n) for n = 21523299 and 21523308.

It is not an unprimeable number, because it can be changed into a prime (21523339) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 896794 + ... + 896817.

Almost surely, 2^21523332 is an apocalyptic number.

It is an amenable number.

21523332 is an abundant number, since it is smaller than the sum of its proper divisors (28697804).

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

21523332 is a wasteful number, since it uses less digits than its factorization.

21523332 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1793618 (or 1793616 counting only the distinct ones).

The product of its digits is 1080, while the sum is 21.

The square root of 21523332 is about 4639.3245197981. The cubic root of 21523332 is about 278.1654381634.

Adding to 21523332 its reverse (23332512), we get a palindrome (44855844).

The spelling of 21523332 in words is "twenty-one million, five hundred twenty-three thousand, three hundred thirty-two".