400687566 has 8 divisors (see below), whose sum is σ = 801375144. Its totient is φ = 133562520.

The previous prime is 400687543. The next prime is 400687571. The reversal of 400687566 is 665786004.

It is a happy number.

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

400687566 is an admirable number.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

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, 33390625 + ... + 33390636.

It is an arithmetic number, because the mean of its divisors is an integer number (100171893).

Almost surely, 2^400687566 is an apocalyptic number.

400687566 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.

400687566 is a wasteful number, since it uses less digits than its factorization.

400687566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66781266.

The product of its (nonzero) digits is 241920, while the sum is 42.

The square root of 400687566 is about 20017.1817696698. The cubic root of 400687566 is about 737.2282272014.

The spelling of 400687566 in words is "four hundred million, six hundred eighty-seven thousand, five hundred sixty-six".