853681 has 4 divisors (see below), whose sum is σ = 856692. Its totient is φ = 850672.

The previous prime is 853669. The next prime is 853687. The reversal of 853681 is 186358.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 186358 = 2 ⋅93179.

It can be written as a sum of positive squares in 2 ways, for example, as 173056 + 680625 = 416^2 + 825^2 .

It is a cyclic number.

It is not a de Polignac number, because 853681 - 2¹¹ = 851633 is a prime.

It is a super-2 number, since 2×853681² = 1457542499522, which contains 22 as substring.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

853681 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (853687) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1030 + ... + 1663.

It is an arithmetic number, because the mean of its divisors is an integer number (214173).

2⁸⁵³⁶⁸¹ is an apocalyptic number.

It is an amenable number.

853681 is a deficient number, since it is larger than the sum of its proper divisors (3011).

853681 is a wasteful number, since it uses less digits than its factorization.

853681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3010.

The product of its digits is 5760, while the sum is 31.

The square root of 853681 is about 923.9485916435. The cubic root of 853681 is about 94.8633677586.

The spelling of 853681 in words is "eight hundred fifty-three thousand, six hundred eighty-one".