28668563 has 16 divisors (see below), whose sum is σ = 36282624. Its totient is φ = 22001760.

The previous prime is 28668551. The next prime is 28668571. The reversal of 28668563 is 36586682.

It is not a de Polignac number, because 28668563 - 2¹⁰ = 28667539 is a prime.

It is a Smith number, since the sum of its digits (44) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (28668503) 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, 2381 + ... + 7937.

It is an arithmetic number, because the mean of its divisors is an integer number (2267664).

Almost surely, 2^28668563 is an apocalyptic number.

28668563 is a deficient number, since it is larger than the sum of its proper divisors (7614061).

28668563 is a wasteful number, since it uses less digits than its factorization.

28668563 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5642.

The product of its digits is 414720, while the sum is 44.

The square root of 28668563 is about 5354.3032226425. The cubic root of 28668563 is about 306.0567589474.

The spelling of 28668563 in words is "twenty-eight million, six hundred sixty-eight thousand, five hundred sixty-three".