28767217 has 4 divisors (see below), whose sum is σ = 29759220. Its totient is φ = 27775216.

The previous prime is 28767191. The next prime is 28767251. The reversal of 28767217 is 71276782.

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

It can be written as a sum of positive squares in 2 ways, for example, as 14205361 + 14561856 = 3769^2 + 3816^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28767217 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 28767217.

It is not an unprimeable number, because it can be changed into a prime (28767317) 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, 495958 + ... + 496015.

It is an arithmetic number, because the mean of its divisors is an integer number (7439805).

Almost surely, 2^28767217 is an apocalyptic number.

It is an amenable number.

28767217 is a deficient number, since it is larger than the sum of its proper divisors (992003).

28767217 is an equidigital number, since it uses as much as digits as its factorization.

28767217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 992002.

The product of its digits is 65856, while the sum is 40.

The square root of 28767217 is about 5363.5079006188. The cubic root of 28767217 is about 306.4074236045.

The spelling of 28767217 in words is "twenty-eight million, seven hundred sixty-seven thousand, two hundred seventeen".