28704517 has 8 divisors (see below), whose sum is σ = 30442176. Its totient is φ = 26972352.

The previous prime is 28704509. The next prime is 28704523. The reversal of 28704517 is 71540782.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 28704517 - 2³ = 28704509 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28704527) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15208 + ... + 16990.

It is an arithmetic number, because the mean of its divisors is an integer number (3805272).

Almost surely, 2^28704517 is an apocalyptic number.

It is an amenable number.

28704517 is a deficient number, since it is larger than the sum of its proper divisors (1737659).

28704517 is a wasteful number, since it uses less digits than its factorization.

28704517 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2747.

The product of its (nonzero) digits is 15680, while the sum is 34.

The square root of 28704517 is about 5357.6596569771. The cubic root of 28704517 is about 306.1846501128.

The spelling of 28704517 in words is "twenty-eight million, seven hundred four thousand, five hundred seventeen".