28018219 has 4 divisors (see below), whose sum is σ = 28372960. Its totient is φ = 27663480.

The previous prime is 28018187. The next prime is 28018247. The reversal of 28018219 is 91281082.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 28018219 - 2⁵ = 28018187 is a prime.

It is a super-2 number, since 2×28018219² = 1570041191863922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28018259) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 177252 + ... + 177409.

It is an arithmetic number, because the mean of its divisors is an integer number (7093240).

Almost surely, 2^28018219 is an apocalyptic number.

28018219 is a deficient number, since it is larger than the sum of its proper divisors (354741).

28018219 is an equidigital number, since it uses as much as digits as its factorization.

28018219 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 354740.

The product of its (nonzero) digits is 2304, while the sum is 31.

The square root of 28018219 is about 5293.2238758624. The cubic root of 28018219 is about 303.7247443537.

The spelling of 28018219 in words is "twenty-eight million, eighteen thousand, two hundred nineteen".