28665217 has 8 divisors (see below), whose sum is σ = 32970176. Its totient is φ = 24412752.

The previous prime is 28665211. The next prime is 28665223. The reversal of 28665217 is 71256682.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (28665211) and next prime (28665223).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 28665217 - 2¹⁹ = 28140929 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28665211) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11943 + ... + 14140.

It is an arithmetic number, because the mean of its divisors is an integer number (4121272).

Almost surely, 2^28665217 is an apocalyptic number.

It is an amenable number.

28665217 is a deficient number, since it is larger than the sum of its proper divisors (4304959).

28665217 is a wasteful number, since it uses less digits than its factorization.

28665217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26247.

The product of its digits is 40320, while the sum is 37.

The square root of 28665217 is about 5353.9907545680. The cubic root of 28665217 is about 306.0448515286.

It can be divided in two parts, 28665 and 217, that added together give a palindrome (28882).

The spelling of 28665217 in words is "twenty-eight million, six hundred sixty-five thousand, two hundred seventeen".