28218023 has 4 divisors (see below), whose sum is σ = 28232040. Its totient is φ = 28204008.

The previous prime is 28218017. The next prime is 28218053. The reversal of 28218023 is 32081282.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 32081282 = 2 ⋅16040641.

It is a cyclic number.

It is not a de Polignac number, because 28218023 - 2⁴ = 28218007 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28217983 and 28218001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28218053) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3353 + ... + 8226.

It is an arithmetic number, because the mean of its divisors is an integer number (7058010).

Almost surely, 2^28218023 is an apocalyptic number.

28218023 is a deficient number, since it is larger than the sum of its proper divisors (14017).

28218023 is a wasteful number, since it uses less digits than its factorization.

28218023 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14016.

The product of its (nonzero) digits is 1536, while the sum is 26.

The square root of 28218023 is about 5312.0639115131. The cubic root of 28218023 is about 304.4450106203.

The spelling of 28218023 in words is "twenty-eight million, two hundred eighteen thousand, twenty-three".