28276281 has 48 divisors (see below), whose sum is σ = 46725120. Its totient is φ = 16328160.

The previous prime is 28276277. The next prime is 28276307. The reversal of 28276281 is 18267282.

It is a happy number.

28276281 is a `hidden beast` number, since 2 + 8 + 27 + 628 + 1 = 666.

It is not a de Polignac number, because 28276281 - 2² = 28276277 is a prime.

It is a super-2 number, since 2×28276281² = 1599096134381922, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (28276201) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 274476 + ... + 274578.

It is an arithmetic number, because the mean of its divisors is an integer number (973440).

Almost surely, 2^28276281 is an apocalyptic number.

It is an amenable number.

28276281 is a deficient number, since it is larger than the sum of its proper divisors (18448839).

28276281 is a wasteful number, since it uses less digits than its factorization.

28276281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 226 (or 223 counting only the distinct ones).

The product of its digits is 21504, while the sum is 36.

The square root of 28276281 is about 5317.5446401511. The cubic root of 28276281 is about 304.6543823097.

The spelling of 28276281 in words is "twenty-eight million, two hundred seventy-six thousand, two hundred eighty-one".