844640 has 24 divisors (see below), whose sum is σ = 1995840. Its totient is φ = 337792.

The previous prime is 844639. The next prime is 844643. The reversal of 844640 is 46448.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (844643) 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, 2480 + ... + 2799.

It is an arithmetic number, because the mean of its divisors is an integer number (83160).

2⁸⁴⁴⁶⁴⁰ is an apocalyptic number.

844640 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

844640 is an abundant number, since it is smaller than the sum of its proper divisors (1151200).

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

844640 is a wasteful number, since it uses less digits than its factorization.

844640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5294 (or 5286 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 26.

The square root of 844640 is about 919.0429804966. The cubic root of 844640 is about 94.5272916518.

The spelling of 844640 in words is "eight hundred forty-four thousand, six hundred forty".