842857 has 2 divisors, whose sum is σ = 842858. Its totient is φ = 842856.

The previous prime is 842819. The next prime is 842869. The reversal of 842857 is 758248.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 737881 + 104976 = 859^2 + 324^2 .

It is a cyclic number.

It is not a de Polignac number, because 842857 - 2⁷ = 842729 is a prime.

It is not a weakly prime, because it can be changed into another prime (842887) 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, 421428 + 421429.

It is an arithmetic number, because the mean of its divisors is an integer number (421429).

2⁸⁴²⁸⁵⁷ is an apocalyptic number.

It is an amenable number.

842857 is a deficient number, since it is larger than the sum of its proper divisors (1).

842857 is an equidigital number, since it uses as much as digits as its factorization.

842857 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 17920, while the sum is 34.

The square root of 842857 is about 918.0724372292. The cubic root of 842857 is about 94.4607303967.

The spelling of 842857 in words is "eight hundred forty-two thousand, eight hundred fifty-seven".