28118505 has 16 divisors (see below), whose sum is σ = 45607680. Its totient is φ = 14790528.

The previous prime is 28118479. The next prime is 28118507. The reversal of 28118505 is 50581182.

It is not a de Polignac number, because 28118505 - 2⁵ = 28118473 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28118507) 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, 11745 + ... + 13934.

It is an arithmetic number, because the mean of its divisors is an integer number (2850480).

Almost surely, 2^28118505 is an apocalyptic number.

It is an amenable number.

28118505 is a deficient number, since it is larger than the sum of its proper divisors (17489175).

28118505 is a wasteful number, since it uses less digits than its factorization.

28118505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25760.

The product of its (nonzero) digits is 3200, while the sum is 30.

The square root of 28118505 is about 5302.6884690693. The cubic root of 28118505 is about 304.0866882567.

Adding to 28118505 its reverse (50581182), we get a palindrome (78699687).

The spelling of 28118505 in words is "twenty-eight million, one hundred eighteen thousand, five hundred five".