28349813 has 2 divisors, whose sum is σ = 28349814. Its totient is φ = 28349812.

The previous prime is 28349759. The next prime is 28349833. The reversal of 28349813 is 31894382.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 24671089 + 3678724 = 4967^2 + 1918^2 .

It is a cyclic number.

It is not a de Polignac number, because 28349813 - 2²⁰ = 27301237 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28349833) 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, 14174906 + 14174907.

It is an arithmetic number, because the mean of its divisors is an integer number (14174907).

Almost surely, 2^28349813 is an apocalyptic number.

It is an amenable number.

28349813 is a deficient number, since it is larger than the sum of its proper divisors (1).

28349813 is an equidigital number, since it uses as much as digits as its factorization.

28349813 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 41472, while the sum is 38.

The square root of 28349813 is about 5324.4542443334. The cubic root of 28349813 is about 304.9182366158.

The spelling of 28349813 in words is "twenty-eight million, three hundred forty-nine thousand, eight hundred thirteen".