28128728226 has 16 divisors (see below), whose sum is σ = 57777928704. Its totient is φ = 9122830704.

The previous prime is 28128728219. The next prime is 28128728227. The reversal of 28128728226 is 62282782182.

It is a super-2 number, since 2×28128728226² (a number of 22 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (28128728227) 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, 63352770 + ... + 63353213.

It is an arithmetic number, because the mean of its divisors is an integer number (3611120544).

Almost surely, 2^28128728226 is an apocalyptic number.

28128728226 is an abundant number, since it is smaller than the sum of its proper divisors (29649200478).

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

28128728226 is a wasteful number, since it uses less digits than its factorization.

28128728226 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126706025.

The product of its digits is 688128, while the sum is 48.

The spelling of 28128728226 in words is "twenty-eight billion, one hundred twenty-eight million, seven hundred twenty-eight thousand, two hundred twenty-six".