28188567972 has 30 divisors (see below), whose sum is σ = 73690485638. Its totient is φ = 9396189216.

The previous prime is 28188567949. The next prime is 28188568013. The reversal of 28188567972 is 27976588182.

It can be written as a sum of positive squares in only one way, i.e., 24936831396 + 3251736576 = 157914^2 + 57024^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 43500553 + ... + 43501200.

Almost surely, 2^28188567972 is an apocalyptic number.

It is an amenable number.

28188567972 is an abundant number, since it is smaller than the sum of its proper divisors (45501917666).

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

28188567972 is a wasteful number, since it uses less digits than its factorization.

28188567972 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 87001769 (or 87001758 counting only the distinct ones).

The product of its digits is 27095040, while the sum is 63.

The spelling of 28188567972 in words is "twenty-eight billion, one hundred eighty-eight million, five hundred sixty-seven thousand, nine hundred seventy-two".