809844 has 48 divisors (see below), whose sum is σ = 2236416. Its totient is φ = 223200.

The previous prime is 809843. The next prime is 809869. The reversal of 809844 is 448908.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (809843) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 2449 + ... + 2759.

It is an arithmetic number, because the mean of its divisors is an integer number (46592).

2⁸⁰⁹⁸⁴⁴ is an apocalyptic number.

809844 is a gapful number since it is divisible by the number (84) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 809844, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1118208).

809844 is an abundant number, since it is smaller than the sum of its proper divisors (1426572).

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

809844 is a wasteful number, since it uses less digits than its factorization.

809844 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 356 (or 354 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 33.

The square root of 809844 is about 899.9133291601. The cubic root of 809844 is about 93.2109904948.

It can be divided in two parts, 809 and 844, that added together give a triangular number (1653 = T₅₇).

The spelling of 809844 in words is "eight hundred nine thousand, eight hundred forty-four".