857281 has 2 divisors, whose sum is σ = 857282. Its totient is φ = 857280.

The previous prime is 857273. The next prime is 857287. The reversal of 857281 is 182758.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 839056 + 18225 = 916^2 + 135^2 .

It is a cyclic number.

It is not a de Polignac number, because 857281 - 2³ = 857273 is a prime.

It is a super-2 number, since 2×857281² = 1469861425922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (857287) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 428640 + 428641.

It is an arithmetic number, because the mean of its divisors is an integer number (428641).

2⁸⁵⁷²⁸¹ is an apocalyptic number.

It is an amenable number.

857281 is a deficient number, since it is larger than the sum of its proper divisors (1).

857281 is an equidigital number, since it uses as much as digits as its factorization.

857281 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4480, while the sum is 31.

The square root of 857281 is about 925.8947024365. The cubic root of 857281 is about 94.9965280356.

The spelling of 857281 in words is "eight hundred fifty-seven thousand, two hundred eighty-one".