849864217 has 2 divisors, whose sum is σ = 849864218. Its totient is φ = 849864216.

The previous prime is 849864181. The next prime is 849864229. The reversal of 849864217 is 712468948.

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., 604127241 + 245736976 = 24579^2 + 15676^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-849864217 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (849864317) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 424932108 + 424932109.

It is an arithmetic number, because the mean of its divisors is an integer number (424932109).

Almost surely, 2^849864217 is an apocalyptic number.

It is an amenable number.

849864217 is a deficient number, since it is larger than the sum of its proper divisors (1).

849864217 is an equidigital number, since it uses as much as digits as its factorization.

849864217 is an evil number, because the sum of its binary digits is even.

The product of its digits is 774144, while the sum is 49.

The square root of 849864217 is about 29152.4307219827. The cubic root of 849864217 is about 947.2177941378.

The spelling of 849864217 in words is "eight hundred forty-nine million, eight hundred sixty-four thousand, two hundred seventeen".