28120219 has 4 divisors (see below), whose sum is σ = 28806120. Its totient is φ = 27434320.

The previous prime is 28120217. The next prime is 28120229. The reversal of 28120219 is 91202182.

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 28120219 - 2¹ = 28120217 is a prime.

It is a super-2 number, since 2×28120219² = 1581493433215922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28120193 and 28120202.

It is not an unprimeable number, because it can be changed into a prime (28120217) 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, 342889 + ... + 342970.

It is an arithmetic number, because the mean of its divisors is an integer number (7201530).

Almost surely, 2^28120219 is an apocalyptic number.

28120219 is a deficient number, since it is larger than the sum of its proper divisors (685901).

28120219 is an equidigital number, since it uses as much as digits as its factorization.

28120219 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 685900.

The product of its (nonzero) digits is 576, while the sum is 25.

The square root of 28120219 is about 5302.8500827385. The cubic root of 28120219 is about 304.0928667976.

The spelling of 28120219 in words is "twenty-eight million, one hundred twenty thousand, two hundred nineteen".