405844 has 12 divisors (see below), whose sum is σ = 714868. Its totient is φ = 201600.

The previous prime is 405829. The next prime is 405857. The reversal of 405844 is 448504.

It can be written as a sum of positive squares in 2 ways, for example, as 114244 + 291600 = 338^2 + 540^2 .

It is a congruent number.

It is an unprimeable number.

405844 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 754 + ... + 1174.

2⁴⁰⁵⁸⁴⁴ is an apocalyptic number.

It is an amenable number.

405844 is a deficient number, since it is larger than the sum of its proper divisors (309024).

405844 is a wasteful number, since it uses less digits than its factorization.

405844 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 666 (or 664 counting only the distinct ones).

The product of its (nonzero) digits is 2560, while the sum is 25.

The square root of 405844 is about 637.0588669817. The cubic root of 405844 is about 74.0377212116.

The spelling of 405844 in words is "four hundred five thousand, eight hundred forty-four".