28218113 has 16 divisors (see below), whose sum is σ = 37252224. Its totient is φ = 20693760.

The previous prime is 28218109. The next prime is 28218121. The reversal of 28218113 is 31181282.

It is not a de Polignac number, because 28218113 - 2² = 28218109 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28218103) 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 15 ways as a sum of consecutive naturals, for example, 9470 + ... + 12087.

It is an arithmetic number, because the mean of its divisors is an integer number (2328264).

Almost surely, 2^28218113 is an apocalyptic number.

It is an amenable number.

28218113 is a deficient number, since it is larger than the sum of its proper divisors (9034111).

28218113 is a wasteful number, since it uses less digits than its factorization.

28218113 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21592.

The product of its digits is 768, while the sum is 26.

The square root of 28218113 is about 5312.0723827900. The cubic root of 28218113 is about 304.4453342907.

Adding to 28218113 its reverse (31181282), we get a palindrome (59399395).

The spelling of 28218113 in words is "twenty-eight million, two hundred eighteen thousand, one hundred thirteen".