22815728 has 40 divisors (see below), whose sum is σ = 47913600. Its totient is φ = 10462464.

The previous prime is 22815691. The next prime is 22815731. The reversal of 22815728 is 82751822.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 47393 + ... + 47871.

It is an arithmetic number, because the mean of its divisors is an integer number (1197840).

Almost surely, 2^22815728 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 22815728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23956800).

22815728 is an abundant number, since it is smaller than the sum of its proper divisors (25097872).

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

22815728 is a wasteful number, since it uses less digits than its factorization.

22815728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 729 (or 723 counting only the distinct ones).

The product of its digits is 17920, while the sum is 35.

The square root of 22815728 is about 4776.5812041668. The cubic root of 22815728 is about 283.6251750313.

The spelling of 22815728 in words is "twenty-two million, eight hundred fifteen thousand, seven hundred twenty-eight".