28186841 has 4 divisors (see below), whose sum is σ = 28198884. Its totient is φ = 28174800.

The previous prime is 28186813. The next prime is 28186849. The reversal of 28186841 is 14868182.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 16483600 + 11703241 = 4060^2 + 3421^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28186841 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28186795 and 28186804.

It is not an unprimeable number, because it can be changed into a prime (28186849) 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, 1250 + ... + 7611.

It is an arithmetic number, because the mean of its divisors is an integer number (7049721).

Almost surely, 2^28186841 is an apocalyptic number.

It is an amenable number.

28186841 is a deficient number, since it is larger than the sum of its proper divisors (12043).

28186841 is an equidigital number, since it uses as much as digits as its factorization.

28186841 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12042.

The product of its digits is 24576, while the sum is 38.

The square root of 28186841 is about 5309.1280828400. The cubic root of 28186841 is about 304.3328281420.

The spelling of 28186841 in words is "twenty-eight million, one hundred eighty-six thousand, eight hundred forty-one".