28308747 has 4 divisors (see below), whose sum is σ = 37745000. Its totient is φ = 18872496.

The previous prime is 28308739. The next prime is 28308767. The reversal of 28308747 is 74780382.

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

It is not a de Polignac number, because 28308747 - 2³ = 28308739 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28308767) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4718122 + ... + 4718127.

It is an arithmetic number, because the mean of its divisors is an integer number (9436250).

Almost surely, 2^28308747 is an apocalyptic number.

28308747 is a deficient number, since it is larger than the sum of its proper divisors (9436253).

28308747 is an equidigital number, since it uses as much as digits as its factorization.

28308747 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9436252.

The product of its (nonzero) digits is 75264, while the sum is 39.

The square root of 28308747 is about 5320.5964891166. The cubic root of 28308747 is about 304.7709361345.

The spelling of 28308747 in words is "twenty-eight million, three hundred eight thousand, seven hundred forty-seven".