21332528 has 40 divisors (see below), whose sum is σ = 47854080. Its totient is φ = 9023040.

The previous prime is 21332527. The next prime is 21332537. The reversal of 21332528 is 82523312.

It is a junction number, because it is equal to n+sod(n) for n = 21332497 and 21332506.

It is not an unprimeable number, because it can be changed into a prime (21332527) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7643 + ... + 10053.

It is an arithmetic number, because the mean of its divisors is an integer number (1196352).

Almost surely, 2^21332528 is an apocalyptic number.

21332528 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21332528, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23927040).

21332528 is an abundant number, since it is smaller than the sum of its proper divisors (26521552).

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

21332528 is a wasteful number, since it uses less digits than its factorization.

21332528 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2505 (or 2499 counting only the distinct ones).

The product of its digits is 2880, while the sum is 26.

The square root of 21332528 is about 4618.7149728036. The cubic root of 21332528 is about 277.3410197779.

The spelling of 21332528 in words is "twenty-one million, three hundred thirty-two thousand, five hundred twenty-eight".