28308815 has 8 divisors (see below), whose sum is σ = 34132848. Its totient is φ = 22538880.

The previous prime is 28308793. The next prime is 28308821. The reversal of 28308815 is 51880382.

28308815 is nontrivially palindromic in base 14.

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

It is not a de Polignac number, because 28308815 - 2⁸ = 28308559 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12362 + ... + 14471.

It is an arithmetic number, because the mean of its divisors is an integer number (4266606).

Almost surely, 2^28308815 is an apocalyptic number.

28308815 is a deficient number, since it is larger than the sum of its proper divisors (5824033).

28308815 is a wasteful number, since it uses less digits than its factorization.

28308815 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27049.

The product of its (nonzero) digits is 15360, while the sum is 35.

The square root of 28308815 is about 5320.6028793737. The cubic root of 28308815 is about 304.7711801628.

The spelling of 28308815 in words is "twenty-eight million, three hundred eight thousand, eight hundred fifteen".