844840 has 16 divisors (see below), whose sum is σ = 1900980. Its totient is φ = 337920.

The previous prime is 844777. The next prime is 844841. The reversal of 844840 is 48448.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 842724 + 2116 = 918^2 + 46^2 .

It is a junction number, because it is equal to n+sod(n) for n = 844799 and 844808.

It is not an unprimeable number, because it can be changed into a prime (844841) 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, 10521 + ... + 10600.

2⁸⁴⁴⁸⁴⁰ is an apocalyptic number.

It is an amenable number.

844840 is an abundant number, since it is smaller than the sum of its proper divisors (1056140).

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

844840 is a wasteful number, since it uses less digits than its factorization.

844840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21132 (or 21128 counting only the distinct ones).

The product of its (nonzero) digits is 4096, while the sum is 28.

The square root of 844840 is about 919.1517828955. The cubic root of 844840 is about 94.5347520161.

The spelling of 844840 in words is "eight hundred forty-four thousand, eight hundred forty".