28286866969 has 9 divisors (see below), whose sum is σ = 28567274463. Its totient is φ = 28009190232.

The previous prime is 28286866921. The next prime is 28286866997. The reversal of 28286866969 is 96966868282.

The square root of 28286866969 is 168187.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 19715810569 + 8571056400 = 140413^2 + 92580^2 .

It is not a de Polignac number, because 28286866969 - 2⁷ = 28286866841 is a prime.

It is a super-2 number, since 2×28286866969² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28286866898 and 28286866907.

It is not an unprimeable number, because it can be changed into a prime (28286866999) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 18331612 + ... + 18333154.

It is an arithmetic number, because the mean of its divisors is an integer number (3174141607).

Almost surely, 2^28286866969 is an apocalyptic number.

28286866969 is the 168187-th square number.

28286866969 is the 84094-th centered octagonal number.

It is an amenable number.

28286866969 is a deficient number, since it is larger than the sum of its proper divisors (280407494).

28286866969 is an frugal number, since it uses more digits than its factorization.

28286866969 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3304 (or 1652 counting only the distinct ones).

The product of its digits is 214990848, while the sum is 70.

The spelling of 28286866969 in words is "twenty-eight billion, two hundred eighty-six million, eight hundred sixty-six thousand, nine hundred sixty-nine".