405660 has 24 divisors (see below), whose sum is σ = 1136016. Its totient is φ = 108160.

The previous prime is 405659. The next prime is 405667. The reversal of 405660 is 66504.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (405667) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3321 + ... + 3440.

It is an arithmetic number, because the mean of its divisors is an integer number (47334).

2⁴⁰⁵⁶⁶⁰ is an apocalyptic number.

It is an amenable number.

405660 is an abundant number, since it is smaller than the sum of its proper divisors (730356).

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

405660 is a wasteful number, since it uses less digits than its factorization.

405660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6773 (or 6771 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 21.

The square root of 405660 is about 636.9144369537. The cubic root of 405660 is about 74.0265305407.

The spelling of 405660 in words is "four hundred five thousand, six hundred sixty".