28218013 has 8 divisors (see below), whose sum is σ = 29111040. Its totient is φ = 27331920.

The previous prime is 28218007. The next prime is 28218017. The reversal of 28218013 is 31081282.

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

It is a cyclic number.

It is not a de Polignac number, because 28218013 - 2¹³ = 28209821 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 (28218017) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7248 + ... + 10438.

It is an arithmetic number, because the mean of its divisors is an integer number (3638880).

Almost surely, 2^28218013 is an apocalyptic number.

It is an amenable number.

28218013 is a deficient number, since it is larger than the sum of its proper divisors (893027).

28218013 is a wasteful number, since it uses less digits than its factorization.

28218013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3467.

The product of its (nonzero) digits is 768, while the sum is 25.

The square root of 28218013 is about 5312.0629702593. The cubic root of 28218013 is about 304.4449746569. Note that the first 3 decimals are identical.

Adding to 28218013 its reverse (31081282), we get a palindrome (59299295).

The spelling of 28218013 in words is "twenty-eight million, two hundred eighteen thousand, thirteen".