400566 has 16 divisors (see below), whose sum is σ = 810288. Its totient is φ = 132000.

The previous prime is 400559. The next prime is 400579. The reversal of 400566 is 665004.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 276 + ... + 936.

It is an arithmetic number, because the mean of its divisors is an integer number (50643).

2⁴⁰⁰⁵⁶⁶ is an apocalyptic number.

400566 is an abundant number, since it is smaller than the sum of its proper divisors (409722).

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

400566 is a wasteful number, since it uses less digits than its factorization.

400566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 767.

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

The square root of 400566 is about 632.9028361447. The cubic root of 400566 is about 73.7153662911.

The spelling of 400566 in words is "four hundred thousand, five hundred sixty-six".