22231728 has 30 divisors (see below), whose sum is σ = 62218364. Its totient is φ = 7410528.

The previous prime is 22231723. The next prime is 22231757. The reversal of 22231728 is 82713222.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (22231723) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 77050 + ... + 77337.

Almost surely, 2^22231728 is an apocalyptic number.

It is an amenable number.

22231728 is an abundant number, since it is smaller than the sum of its proper divisors (39986636).

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

22231728 is a wasteful number, since it uses less digits than its factorization.

22231728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 154401 (or 154392 counting only the distinct ones).

The product of its digits is 2688, while the sum is 27.

The square root of 22231728 is about 4715.0533401013. The cubic root of 22231728 is about 281.1843034701.

The spelling of 22231728 in words is "twenty-two million, two hundred thirty-one thousand, seven hundred twenty-eight".