405642 has 8 divisors (see below), whose sum is σ = 811296. Its totient is φ = 135212.

The previous prime is 405641. The next prime is 405659. The reversal of 405642 is 246504.

It is a happy number.

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

405642 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (405641) 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, 33798 + ... + 33809.

It is an arithmetic number, because the mean of its divisors is an integer number (101412).

2⁴⁰⁵⁶⁴² is an apocalyptic number.

405642 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.

405642 is a wasteful number, since it uses less digits than its factorization.

405642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67612.

The product of its (nonzero) digits is 960, while the sum is 21.

The square root of 405642 is about 636.9003061704. The cubic root of 405642 is about 74.0254356194.

The spelling of 405642 in words is "four hundred five thousand, six hundred forty-two".