857321 has 2 divisors, whose sum is σ = 857322. Its totient is φ = 857320.

The previous prime is 857309. The next prime is 857333. The reversal of 857321 is 123758.

857321 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a balanced prime because it is at equal distance from previous prime (857309) and next prime (857333).

It can be written as a sum of positive squares in only one way, i.e., 570025 + 287296 = 755^2 + 536^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-857321 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (857341) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 428660 + 428661.

It is an arithmetic number, because the mean of its divisors is an integer number (428661).

2⁸⁵⁷³²¹ is an apocalyptic number.

It is an amenable number.

857321 is a deficient number, since it is larger than the sum of its proper divisors (1).

857321 is an equidigital number, since it uses as much as digits as its factorization.

857321 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1680, while the sum is 26.

The square root of 857321 is about 925.9163029130. The cubic root of 857321 is about 94.9980054983.

The spelling of 857321 in words is "eight hundred fifty-seven thousand, three hundred twenty-one".