857218 has 8 divisors (see below), whose sum is σ = 1297548. Its totient is φ = 424704.

The previous prime is 857203. The next prime is 857221. The reversal of 857218 is 812758.

It can be written as a sum of positive squares in 2 ways, for example, as 660969 + 196249 = 813^2 + 443^2 .

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

It is a self number, because there is not a number n which added to its sum of digits gives 857218.

It is a congruent number.

It is an unprimeable number.

857218 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

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 3 ways as a sum of consecutive naturals, for example, 1671 + ... + 2122.

2⁸⁵⁷²¹⁸ is an apocalyptic number.

857218 is a deficient number, since it is larger than the sum of its proper divisors (440330).

857218 is a wasteful number, since it uses less digits than its factorization.

857218 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3908.

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

The square root of 857218 is about 925.8606806642. The cubic root of 857218 is about 94.9942009387.

The spelling of 857218 in words is "eight hundred fifty-seven thousand, two hundred eighteen".