857217 has 8 divisors (see below), whose sum is σ = 1150624. Its totient is φ = 567648.

The previous prime is 857203. The next prime is 857221. The reversal of 857217 is 712758.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 857217 - 2⁴ = 857201 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (857267) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 388 + ... + 1365.

It is an arithmetic number, because the mean of its divisors is an integer number (143828).

2⁸⁵⁷²¹⁷ is an apocalyptic number.

It is an amenable number.

857217 is a deficient number, since it is larger than the sum of its proper divisors (293407).

857217 is a wasteful number, since it uses less digits than its factorization.

857217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1919.

The product of its digits is 3920, while the sum is 30.

The square root of 857217 is about 925.8601406260. The cubic root of 857217 is about 94.9941639998.

The spelling of 857217 in words is "eight hundred fifty-seven thousand, two hundred seventeen".