400666 has 8 divisors (see below), whose sum is σ = 686880. Its totient is φ = 171708.

The previous prime is 400657. The next prime is 400679. The reversal of 400666 is 666004.

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

400666 is a modest number, since divided by 666 gives 400 as remainder.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14296 + ... + 14323.

It is an arithmetic number, because the mean of its divisors is an integer number (85860).

2⁴⁰⁰⁶⁶⁶ is an apocalyptic number.

400666 is a deficient number, since it is larger than the sum of its proper divisors (286214).

400666 is a wasteful number, since it uses less digits than its factorization.

400666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28628.

The product of its (nonzero) digits is 864, while the sum is 22.

The square root of 400666 is about 632.9818322827. The cubic root of 400666 is about 73.7215000479.

The spelling of 400666 in words is "four hundred thousand, six hundred sixty-six".