844721 has 8 divisors (see below), whose sum is σ = 928320. Its totient is φ = 765072.

The previous prime is 844717. The next prime is 844733. The reversal of 844721 is 127448.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 844721 - 2² = 844717 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (844771) 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 7 ways as a sum of consecutive naturals, for example, 530 + ... + 1403.

It is an arithmetic number, because the mean of its divisors is an integer number (116040).

2⁸⁴⁴⁷²¹ is an apocalyptic number.

It is an amenable number.

844721 is a deficient number, since it is larger than the sum of its proper divisors (83599).

844721 is a wasteful number, since it uses less digits than its factorization.

844721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1975.

The product of its digits is 1792, while the sum is 26.

The square root of 844721 is about 919.0870470200. The cubic root of 844721 is about 94.5303132412.

The spelling of 844721 in words is "eight hundred forty-four thousand, seven hundred twenty-one".