405889 has 4 divisors (see below), whose sum is σ = 442800. Its totient is φ = 368980.

The previous prime is 405871. The next prime is 405893. The reversal of 405889 is 988504.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 405889 - 2⁵ = 405857 is a prime.

It is a Duffinian number.

405889 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (405829) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18439 + ... + 18460.

It is an arithmetic number, because the mean of its divisors is an integer number (110700).

2⁴⁰⁵⁸⁸⁹ is an apocalyptic number.

It is an amenable number.

405889 is a deficient number, since it is larger than the sum of its proper divisors (36911).

405889 is a wasteful number, since it uses less digits than its factorization.

405889 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36910.

The product of its (nonzero) digits is 11520, while the sum is 34.

The square root of 405889 is about 637.0941845599. The cubic root of 405889 is about 74.0404575457.

It can be divided in two parts, 40 and 5889, that added together give a square (5929 = 77²).

The spelling of 405889 in words is "four hundred five thousand, eight hundred eighty-nine".