28680817 has 4 divisors (see below), whose sum is σ = 31288176. Its totient is φ = 26073460.

The previous prime is 28680811. The next prime is 28680829. The reversal of 28680817 is 71808682.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28680817 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28680817.

It is not an unprimeable number, because it can be changed into a prime (28680811) 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, 1303663 + ... + 1303684.

It is an arithmetic number, because the mean of its divisors is an integer number (7822044).

Almost surely, 2^28680817 is an apocalyptic number.

It is an amenable number.

28680817 is a deficient number, since it is larger than the sum of its proper divisors (2607359).

28680817 is a wasteful number, since it uses less digits than its factorization.

28680817 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2607358.

The product of its (nonzero) digits is 43008, while the sum is 40.

The square root of 28680817 is about 5355.4474136154. The cubic root of 28680817 is about 306.1003593806.

The spelling of 28680817 in words is "twenty-eight million, six hundred eighty thousand, eight hundred seventeen".