28727813 has 2 divisors, whose sum is σ = 28727814. Its totient is φ = 28727812.

The previous prime is 28727801. The next prime is 28727819. The reversal of 28727813 is 31872782.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 26604964 + 2122849 = 5158^2 + 1457^2 .

It is a cyclic number.

It is not a de Polignac number, because 28727813 - 2⁸ = 28727557 is a prime.

It is a Sophie Germain prime.

It is a Chen 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 (28727819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14363906 + 14363907.

It is an arithmetic number, because the mean of its divisors is an integer number (14363907).

Almost surely, 2^28727813 is an apocalyptic number.

It is an amenable number.

28727813 is a deficient number, since it is larger than the sum of its proper divisors (1).

28727813 is an equidigital number, since it uses as much as digits as its factorization.

28727813 is an evil number, because the sum of its binary digits is even.

The product of its digits is 37632, while the sum is 38.

The square root of 28727813 is about 5359.8332996465. The cubic root of 28727813 is about 306.2674587853.

The spelling of 28727813 in words is "twenty-eight million, seven hundred twenty-seven thousand, eight hundred thirteen".