400845666 has 16 divisors (see below), whose sum is σ = 863360064. Its totient is φ = 123337104.

The previous prime is 400845659. The next prime is 400845667. The reversal of 400845666 is 666548004.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is not an unprimeable number, because it can be changed into a prime (400845667) 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, 2569446 + ... + 2569601.

It is an arithmetic number, because the mean of its divisors is an integer number (53960004).

Almost surely, 2^400845666 is an apocalyptic number.

400845666 is an abundant number, since it is smaller than the sum of its proper divisors (462514398).

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

400845666 is a wasteful number, since it uses less digits than its factorization.

400845666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5139065.

The product of its (nonzero) digits is 138240, while the sum is 39.

The square root of 400845666 is about 20021.1304875624. The cubic root of 400845666 is about 737.3251775988.

The spelling of 400845666 in words is "four hundred million, eight hundred forty-five thousand, six hundred sixty-six".