405409 has 4 divisors (see below), whose sum is σ = 416404. Its totient is φ = 394416.

The previous prime is 405407. The next prime is 405413. The reversal of 405409 is 904504.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 313600 + 91809 = 560^2 + 303^2 .

It is a cyclic number.

It is not a de Polignac number, because 405409 - 2¹ = 405407 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 405409.

It is not an unprimeable number, because it can be changed into a prime (405401) 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, 5442 + ... + 5515.

It is an arithmetic number, because the mean of its divisors is an integer number (104101).

2⁴⁰⁵⁴⁰⁹ is an apocalyptic number.

It is an amenable number.

405409 is a deficient number, since it is larger than the sum of its proper divisors (10995).

405409 is a wasteful number, since it uses less digits than its factorization.

405409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10994.

The product of its (nonzero) digits is 720, while the sum is 22.

The square root of 405409 is about 636.7173627286. The cubic root of 405409 is about 74.0112595480.

The spelling of 405409 in words is "four hundred five thousand, four hundred nine".