28116531 has 16 divisors (see below), whose sum is σ = 41776800. Its totient is φ = 18689184.

The previous prime is 28116527. The next prime is 28116533. The reversal of 28116531 is 13561182.

28116531 is a `hidden beast` number, since 2 + 8 + 1 + 1 + 653 + 1 = 666.

It is not a de Polignac number, because 28116531 - 2² = 28116527 is a prime.

It is a super-2 number, since 2×28116531² = 1581078630947922, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 28116495 and 28116504.

It is not an unprimeable number, because it can be changed into a prime (28116533) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9165 + ... + 11841.

It is an arithmetic number, because the mean of its divisors is an integer number (2611050).

Almost surely, 2^28116531 is an apocalyptic number.

28116531 is a deficient number, since it is larger than the sum of its proper divisors (13660269).

28116531 is a wasteful number, since it uses less digits than its factorization.

28116531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3075 (or 3069 counting only the distinct ones).

The product of its digits is 1440, while the sum is 27.

The square root of 28116531 is about 5302.5023338043. The cubic root of 28116531 is about 304.0795721699.

The spelling of 28116531 in words is "twenty-eight million, one hundred sixteen thousand, five hundred thirty-one".