865306217 has 2 divisors, whose sum is σ = 865306218. Its totient is φ = 865306216.

The previous prime is 865306187. The next prime is 865306219. The reversal of 865306217 is 712603568.

865306217 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 685182976 + 180123241 = 26176^2 + 13421^2 .

It is a cyclic number.

It is not a de Polignac number, because 865306217 - 2¹⁶ = 865240681 is a prime.

Together with 865306219, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (865306219) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 432653108 + 432653109.

It is an arithmetic number, because the mean of its divisors is an integer number (432653109).

Almost surely, 2^865306217 is an apocalyptic number.

It is an amenable number.

865306217 is a deficient number, since it is larger than the sum of its proper divisors (1).

865306217 is an equidigital number, since it uses as much as digits as its factorization.

865306217 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 60480, while the sum is 38.

The square root of 865306217 is about 29416.0877242369. The cubic root of 865306217 is about 952.9203640972.

The spelling of 865306217 in words is "eight hundred sixty-five million, three hundred six thousand, two hundred seventeen".