28166563 has 4 divisors (see below), whose sum is σ = 28339528. Its totient is φ = 27993600.

The previous prime is 28166561. The next prime is 28166629. The reversal of 28166563 is 36566182.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 28166563 - 2¹ = 28166561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28166561) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 86238 + ... + 86563.

It is an arithmetic number, because the mean of its divisors is an integer number (7084882).

Almost surely, 2^28166563 is an apocalyptic number.

28166563 is a deficient number, since it is larger than the sum of its proper divisors (172965).

28166563 is a wasteful number, since it uses less digits than its factorization.

28166563 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 172964.

The product of its digits is 51840, while the sum is 37.

The square root of 28166563 is about 5307.2180094660. The cubic root of 28166563 is about 304.2598302305.

The spelling of 28166563 in words is "twenty-eight million, one hundred sixty-six thousand, five hundred sixty-three".