28508117 has 16 divisors (see below), whose sum is σ = 32052672. Its totient is φ = 25134720.

The previous prime is 28508107. The next prime is 28508141. The reversal of 28508117 is 71180582.

It is a happy number.

It is not a de Polignac number, because 28508117 - 2⁴ = 28508101 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 (28508107) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 62153 + ... + 62609.

It is an arithmetic number, because the mean of its divisors is an integer number (2003292).

Almost surely, 2^28508117 is an apocalyptic number.

It is an amenable number.

28508117 is a deficient number, since it is larger than the sum of its proper divisors (3544555).

28508117 is a wasteful number, since it uses less digits than its factorization.

28508117 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 628.

The product of its (nonzero) digits is 4480, while the sum is 32.

The square root of 28508117 is about 5339.2992985971. The cubic root of 28508117 is about 305.4847331077.

Adding to 28508117 its reverse (71180582), we get a palindrome (99688699).

The spelling of 28508117 in words is "twenty-eight million, five hundred eight thousand, one hundred seventeen".