28089613 has 2 divisors, whose sum is σ = 28089614. Its totient is φ = 28089612.

The previous prime is 28089569. The next prime is 28089631. The reversal of 28089613 is 31698082.

Together with next prime (28089631) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16104169 + 11985444 = 4013^2 + 3462^2 .

It is a cyclic number.

It is not a de Polignac number, because 28089613 - 2⁹ = 28089101 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28089643) 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 as a sum of consecutive naturals, namely, 14044806 + 14044807.

It is an arithmetic number, because the mean of its divisors is an integer number (14044807).

Almost surely, 2^28089613 is an apocalyptic number.

It is an amenable number.

28089613 is a deficient number, since it is larger than the sum of its proper divisors (1).

28089613 is an equidigital number, since it uses as much as digits as its factorization.

28089613 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 20736, while the sum is 37.

The square root of 28089613 is about 5299.9634904403. The cubic root of 28089613 is about 303.9825020226.

It can be divided in two parts, 2808 and 9613, that added together give a palindrome (12421).

The spelling of 28089613 in words is "twenty-eight million, eighty-nine thousand, six hundred thirteen".