28127281 has 8 divisors (see below), whose sum is σ = 34618304. Its totient is φ = 22254480.

The previous prime is 28127273. The next prime is 28127327. The reversal of 28127281 is 18272182.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 28127281 - 2³ = 28127273 is a prime.

It is a super-2 number, since 2×28127281² = 1582287872905922, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (28127221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 154455 + ... + 154636.

It is an arithmetic number, because the mean of its divisors is an integer number (4327288).

Almost surely, 2^28127281 is an apocalyptic number.

It is an amenable number.

28127281 is a deficient number, since it is larger than the sum of its proper divisors (6491023).

28127281 is a wasteful number, since it uses less digits than its factorization.

28127281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 309111.

The product of its digits is 3584, while the sum is 31.

The square root of 28127281 is about 5303.5159092813. The cubic root of 28127281 is about 304.1183208914.

The spelling of 28127281 in words is "twenty-eight million, one hundred twenty-seven thousand, two hundred eighty-one".