28680307 has 4 divisors (see below), whose sum is σ = 28750840. Its totient is φ = 28609776.

The previous prime is 28680299. The next prime is 28680319. The reversal of 28680307 is 70308682.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 28680307 - 2³ = 28680299 is a prime.

It is a super-2 number, since 2×28680307² = 1645120019228498, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28680347) 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, 34653 + ... + 35470.

It is an arithmetic number, because the mean of its divisors is an integer number (7187710).

Almost surely, 2^28680307 is an apocalyptic number.

28680307 is a deficient number, since it is larger than the sum of its proper divisors (70533).

28680307 is an equidigital number, since it uses as much as digits as its factorization.

28680307 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70532.

The product of its (nonzero) digits is 16128, while the sum is 34.

The square root of 28680307 is about 5355.3997983344. The cubic root of 28680307 is about 306.0985450191.

Adding to 28680307 its reverse (70308682), we get a palindrome (98988989).

The spelling of 28680307 in words is "twenty-eight million, six hundred eighty thousand, three hundred seven".