28928297 has 4 divisors (see below), whose sum is σ = 28995540. Its totient is φ = 28861056.

The previous prime is 28928269. The next prime is 28928309. The reversal of 28928297 is 79282982.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 79282982 = 2 ⋅39641491.

It can be written as a sum of positive squares in 2 ways, for example, as 2343961 + 26584336 = 1531^2 + 5156^2 .

It is a cyclic number.

It is not a de Polignac number, because 28928297 - 2⁶ = 28928233 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28928257) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32972 + ... + 33837.

It is an arithmetic number, because the mean of its divisors is an integer number (7248885).

Almost surely, 2^28928297 is an apocalyptic number.

It is an amenable number.

28928297 is a deficient number, since it is larger than the sum of its proper divisors (67243).

28928297 is an equidigital number, since it uses as much as digits as its factorization.

28928297 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67242.

The product of its digits is 290304, while the sum is 47.

The square root of 28928297 is about 5378.5032304536. The cubic root of 28928297 is about 306.9782617138.

The spelling of 28928297 in words is "twenty-eight million, nine hundred twenty-eight thousand, two hundred ninety-seven".