856198417 has 2 divisors, whose sum is σ = 856198418. Its totient is φ = 856198416.

The previous prime is 856198397. The next prime is 856198433. The reversal of 856198417 is 714891658.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 779303056 + 76895361 = 27916^2 + 8769^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-856198417 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (856198457) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 428099208 + 428099209.

It is an arithmetic number, because the mean of its divisors is an integer number (428099209).

Almost surely, 2^856198417 is an apocalyptic number.

It is an amenable number.

856198417 is a deficient number, since it is larger than the sum of its proper divisors (1).

856198417 is an equidigital number, since it uses as much as digits as its factorization.

856198417 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 483840, while the sum is 49.

The square root of 856198417 is about 29260.8683569029. The cubic root of 856198417 is about 949.5652367046.

The spelling of 856198417 in words is "eight hundred fifty-six million, one hundred ninety-eight thousand, four hundred seventeen".