28561117 has 8 divisors (see below), whose sum is σ = 31339224. Its totient is φ = 25866048.

The previous prime is 28561111. The next prime is 28561153. The reversal of 28561117 is 71116582.

It can be written as a sum of positive squares in 4 ways, for example, as 109561 + 28451556 = 331^2 + 5334^2 .

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

It is not a de Polignac number, because 28561117 - 2⁷ = 28560989 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 (28561111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20038 + ... + 21415.

It is an arithmetic number, because the mean of its divisors is an integer number (3917403).

Almost surely, 2^28561117 is an apocalyptic number.

It is an amenable number.

28561117 is a deficient number, since it is larger than the sum of its proper divisors (2778107).

28561117 is a wasteful number, since it uses less digits than its factorization.

28561117 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41519.

The product of its digits is 3360, while the sum is 31.

The square root of 28561117 is about 5344.2601920191. The cubic root of 28561117 is about 305.6739267998.

Adding to 28561117 its reverse (71116582), we get a palindrome (99677699).

The spelling of 28561117 in words is "twenty-eight million, five hundred sixty-one thousand, one hundred seventeen".