843681 has 4 divisors (see below), whose sum is σ = 1124912. Its totient is φ = 562452.

The previous prime is 843679. The next prime is 843701. The reversal of 843681 is 186348.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 843681 - 2¹ = 843679 is a prime.

It is a super-2 number, since 2×843681² = 1423595259522, which contains 22 as substring.

It is a D-number.

It is a Duffinian number.

843681 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (843181) 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, 140611 + ... + 140616.

It is an arithmetic number, because the mean of its divisors is an integer number (281228).

2⁸⁴³⁶⁸¹ is an apocalyptic number.

It is an amenable number.

843681 is a deficient number, since it is larger than the sum of its proper divisors (281231).

843681 is a wasteful number, since it uses less digits than its factorization.

843681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 281230.

The product of its digits is 4608, while the sum is 30.

The square root of 843681 is about 918.5210939331. The cubic root of 843681 is about 94.4915028333.

The spelling of 843681 in words is "eight hundred forty-three thousand, six hundred eighty-one".