857844 has 72 divisors (see below), whose sum is σ = 2459520. Its totient is φ = 258336.

The previous prime is 857839. The next prime is 857851. The reversal of 857844 is 448758.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 857799 and 857808.

It is a congruent number.

It is an unprimeable number.

857844 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 (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 18229 + ... + 18275.

It is an arithmetic number, because the mean of its divisors is an integer number (34160).

2⁸⁵⁷⁸⁴⁴ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 857844, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1229760).

857844 is an abundant number, since it is smaller than the sum of its proper divisors (1601676).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

857844 is a wasteful number, since it uses less digits than its factorization.

857844 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86 (or 65 counting only the distinct ones).

The product of its digits is 35840, while the sum is 36.

The square root of 857844 is about 926.1986827890. The cubic root of 857844 is about 95.0173190954.

The spelling of 857844 in words is "eight hundred fifty-seven thousand, eight hundred forty-four".