21828888 has 48 divisors (see below), whose sum is σ = 59665320. Its totient is φ = 7209216.

The previous prime is 21828881. The next prime is 21828899. The reversal of 21828888 is 88882812.

It is a happy number.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21828881) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6795 + ... + 9477.

Almost surely, 2^21828888 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 21828888, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29832660).

21828888 is an abundant number, since it is smaller than the sum of its proper divisors (37836432).

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

21828888 is a wasteful number, since it uses less digits than its factorization.

21828888 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2808 (or 2801 counting only the distinct ones).

The product of its digits is 131072, while the sum is 45.

The square root of 21828888 is about 4672.1395527103. The cubic root of 21828888 is about 279.4755830493.

The spelling of 21828888 in words is "twenty-one million, eight hundred twenty-eight thousand, eight hundred eighty-eight".