28276531 has 4 divisors (see below), whose sum is σ = 28674864. Its totient is φ = 27878200.

The previous prime is 28276519. The next prime is 28276543. The reversal of 28276531 is 13567282.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13567282 = 2 ⋅6783641.

It is an interprime number because it is at equal distance from previous prime (28276519) and next prime (28276543).

It is a cyclic number.

It is not a de Polignac number, because 28276531 - 2¹¹ = 28274483 is a prime.

It is a super-2 number, since 2×28276531² = 1599124410787922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28276561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 199060 + ... + 199201.

It is an arithmetic number, because the mean of its divisors is an integer number (7168716).

Almost surely, 2^28276531 is an apocalyptic number.

28276531 is a deficient number, since it is larger than the sum of its proper divisors (398333).

28276531 is an equidigital number, since it uses as much as digits as its factorization.

28276531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 398332.

The product of its digits is 20160, while the sum is 34.

The square root of 28276531 is about 5317.5681471891. The cubic root of 28276531 is about 304.6552801573.

The spelling of 28276531 in words is "twenty-eight million, two hundred seventy-six thousand, five hundred thirty-one".