843421 has 4 divisors (see below), whose sum is σ = 893052. Its totient is φ = 793792.

The previous prime is 843397. The next prime is 843443. The reversal of 843421 is 124348.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 225625 + 617796 = 475^2 + 786^2 .

It is a cyclic number.

It is not a de Polignac number, because 843421 - 2¹⁵ = 810653 is a prime.

It is a super-2 number, since 2×843421² = 1422717966482, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 843392 and 843401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (843461) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24790 + ... + 24823.

It is an arithmetic number, because the mean of its divisors is an integer number (223263).

2⁸⁴³⁴²¹ is an apocalyptic number.

It is an amenable number.

843421 is a deficient number, since it is larger than the sum of its proper divisors (49631).

843421 is a wasteful number, since it uses less digits than its factorization.

843421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49630.

The product of its digits is 768, while the sum is 22.

The square root of 843421 is about 918.3795511661. The cubic root of 843421 is about 94.4817952484.

Adding to 843421 its reverse (124348), we get a palindrome (967769).

It can be divided in two parts, 843 and 421, that multiplied together give a triangular number (354903 = T₈₄₂).

The spelling of 843421 in words is "eight hundred forty-three thousand, four hundred twenty-one".