28340813 has 2 divisors, whose sum is σ = 28340814. Its totient is φ = 28340812.

The previous prime is 28340797. The next prime is 28340821. The reversal of 28340813 is 31804382.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18088009 + 10252804 = 4253^2 + 3202^2 .

It is a cyclic number.

It is not a de Polignac number, because 28340813 - 2⁴ = 28340797 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28340413) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14170406 + 14170407.

It is an arithmetic number, because the mean of its divisors is an integer number (14170407).

Almost surely, 2^28340813 is an apocalyptic number.

It is an amenable number.

28340813 is a deficient number, since it is larger than the sum of its proper divisors (1).

28340813 is an equidigital number, since it uses as much as digits as its factorization.

28340813 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4608, while the sum is 29.

The square root of 28340813 is about 5323.6090202042. The cubic root of 28340813 is about 304.8859665078.

The spelling of 28340813 in words is "twenty-eight million, three hundred forty thousand, eight hundred thirteen".