28917227 has 4 divisors (see below), whose sum is σ = 28986336. Its totient is φ = 28848120.

The previous prime is 28917211. The next prime is 28917241. The reversal of 28917227 is 72271982.

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 28917227 - 2⁴ = 28917211 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28910227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 33923 + ... + 34764.

It is an arithmetic number, because the mean of its divisors is an integer number (7246584).

Almost surely, 2^28917227 is an apocalyptic number.

28917227 is a deficient number, since it is larger than the sum of its proper divisors (69109).

28917227 is an equidigital number, since it uses as much as digits as its factorization.

28917227 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69108.

The product of its digits is 28224, while the sum is 38.

The square root of 28917227 is about 5377.4740352697. The cubic root of 28917227 is about 306.9390995638.

The spelling of 28917227 in words is "twenty-eight million, nine hundred seventeen thousand, two hundred twenty-seven".