22728978 has 32 divisors (see below), whose sum is σ = 53169600. Its totient is φ = 7177248.

The previous prime is 22728977. The next prime is 22729019. The reversal of 22728978 is 87982722.

It is a happy number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (22728977) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10051 + ... + 12102.

It is an arithmetic number, because the mean of its divisors is an integer number (1661550).

Almost surely, 2^22728978 is an apocalyptic number.

22728978 is an abundant number, since it is smaller than the sum of its proper divisors (30440622).

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

22728978 is a wasteful number, since it uses less digits than its factorization.

22728978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22183 (or 22177 counting only the distinct ones).

The product of its digits is 225792, while the sum is 45.

The square root of 22728978 is about 4767.4917933857. The cubic root of 22728978 is about 283.2652517698.

It can be divided in two parts, 22 and 728978, that added together give a cube (729000 = 90³).

The spelling of 22728978 in words is "twenty-two million, seven hundred twenty-eight thousand, nine hundred seventy-eight".