28124289 has 12 divisors (see below), whose sum is σ = 40998100. Its totient is φ = 18576864.

The previous prime is 28124221. The next prime is 28124293. The reversal of 28124289 is 98242182.

It can be written as a sum of positive squares in 2 ways, for example, as 21233664 + 6890625 = 4608^2 + 2625^2 .

It is not a de Polignac number, because 28124289 - 2¹⁵ = 28091521 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (28124209) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13354 + ... + 15315.

Almost surely, 2^28124289 is an apocalyptic number.

It is an amenable number.

28124289 is a deficient number, since it is larger than the sum of its proper divisors (12873811).

28124289 is a wasteful number, since it uses less digits than its factorization.

28124289 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28784 (or 28781 counting only the distinct ones).

The product of its digits is 18432, while the sum is 36.

The square root of 28124289 is about 5303.2338247526. The cubic root of 28124289 is about 304.1075371226.

The spelling of 28124289 in words is "twenty-eight million, one hundred twenty-four thousand, two hundred eighty-nine".