28704647 has 4 divisors (see below), whose sum is σ = 28894896. Its totient is φ = 28514400.

The previous prime is 28704631. The next prime is 28704659. The reversal of 28704647 is 74640782.

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 28704647 - 2⁴ = 28704631 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 28704647.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28704677) 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, 94898 + ... + 95199.

It is an arithmetic number, because the mean of its divisors is an integer number (7223724).

Almost surely, 2^28704647 is an apocalyptic number.

28704647 is a deficient number, since it is larger than the sum of its proper divisors (190249).

28704647 is a wasteful number, since it uses less digits than its factorization.

28704647 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 190248.

The product of its (nonzero) digits is 75264, while the sum is 38.

The square root of 28704647 is about 5357.6717891263. The cubic root of 28704647 is about 306.1851123391.

The spelling of 28704647 in words is "twenty-eight million, seven hundred four thousand, six hundred forty-seven".