405906 has 8 divisors (see below), whose sum is σ = 811824. Its totient is φ = 135300.

The previous prime is 405901. The next prime is 405917. The reversal of 405906 is 609504.

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

405906 is an admirable number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 405906.

It is not an unprimeable number, because it can be changed into a prime (405901) by changing a digit.

405906 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, 33820 + ... + 33831.

It is an arithmetic number, because the mean of its divisors is an integer number (101478).

2⁴⁰⁵⁹⁰⁶ is an apocalyptic number.

405906 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

405906 is a wasteful number, since it uses less digits than its factorization.

405906 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67656.

The product of its (nonzero) digits is 1080, while the sum is 24.

The square root of 405906 is about 637.1075262466. The cubic root of 405906 is about 74.0414912193.

The spelling of 405906 in words is "four hundred five thousand, nine hundred six".