28361213 has 2 divisors, whose sum is σ = 28361214. Its totient is φ = 28361212.

The previous prime is 28361197. The next prime is 28361227. The reversal of 28361213 is 31216382.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 28281124 + 80089 = 5318^2 + 283^2 .

It is a cyclic number.

It is not a de Polignac number, because 28361213 - 2⁴ = 28361197 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 (28361233) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14180606 + 14180607.

It is an arithmetic number, because the mean of its divisors is an integer number (14180607).

Almost surely, 2^28361213 is an apocalyptic number.

It is an amenable number.

28361213 is a deficient number, since it is larger than the sum of its proper divisors (1).

28361213 is an equidigital number, since it uses as much as digits as its factorization.

28361213 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1728, while the sum is 26.

The square root of 28361213 is about 5325.5246689880. The cubic root of 28361213 is about 304.9591022830.

Adding to 28361213 its reverse (31216382), we get a palindrome (59577595).

The spelling of 28361213 in words is "twenty-eight million, three hundred sixty-one thousand, two hundred thirteen".