28608961 has 4 divisors (see below), whose sum is σ = 28930500. Its totient is φ = 28287424.

The previous prime is 28608949. The next prime is 28608967. The reversal of 28608961 is 16980682.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 16980682 = 2 ⋅8490341.

It can be written as a sum of positive squares in 2 ways, for example, as 6471936 + 22137025 = 2544^2 + 4705^2 .

It is a cyclic number.

It is not a de Polignac number, because 28608961 - 2⁵ = 28608929 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28608967) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 160636 + ... + 160813.

It is an arithmetic number, because the mean of its divisors is an integer number (7232625).

Almost surely, 2^28608961 is an apocalyptic number.

It is an amenable number.

28608961 is a deficient number, since it is larger than the sum of its proper divisors (321539).

28608961 is an equidigital number, since it uses as much as digits as its factorization.

28608961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 321538.

The product of its (nonzero) digits is 41472, while the sum is 40.

The square root of 28608961 is about 5348.7345232307. The cubic root of 28608961 is about 305.8445142551.

The spelling of 28608961 in words is "twenty-eight million, six hundred eight thousand, nine hundred sixty-one".