21828352 has 72 divisors (see below), whose sum is σ = 53683616. Its totient is φ = 8626176.

The previous prime is 21828349. The next prime is 21828353. The reversal of 21828352 is 25382812.

It is not an unprimeable number, because it can be changed into a prime (21828353) 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, 22828 + ... + 23764.

Almost surely, 2^21828352 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21828352, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26841808).

21828352 is an abundant number, since it is smaller than the sum of its proper divisors (31855264).

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

21828352 is an equidigital number, since it uses as much as digits as its factorization.

21828352 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 973 (or 959 counting only the distinct ones).

The product of its digits is 7680, while the sum is 31.

The square root of 21828352 is about 4672.0821910579. The cubic root of 21828352 is about 279.4732955585.

The spelling of 21828352 in words is "twenty-one million, eight hundred twenty-eight thousand, three hundred fifty-two".