28109267 has 4 divisors (see below), whose sum is σ = 28139016. Its totient is φ = 28079520.

The previous prime is 28109251. The next prime is 28109299. The reversal of 28109267 is 76290182.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 76290182 = 2 ⋅38145091.

It is a cyclic number.

It is not a de Polignac number, because 28109267 - 2⁴ = 28109251 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28109167) 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, 13409 + ... + 15362.

It is an arithmetic number, because the mean of its divisors is an integer number (7034754).

Almost surely, 2^28109267 is an apocalyptic number.

28109267 is a deficient number, since it is larger than the sum of its proper divisors (29749).

28109267 is an equidigital number, since it uses as much as digits as its factorization.

28109267 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29748.

The product of its (nonzero) digits is 12096, while the sum is 35.

The square root of 28109267 is about 5301.8173299351. The cubic root of 28109267 is about 304.0533832556.

The spelling of 28109267 in words is "twenty-eight million, one hundred nine thousand, two hundred sixty-seven".