666430056 has 96 divisors (see below), whose sum is σ = 1947333960. Its totient is φ = 205111296.

The previous prime is 666430027. The next prime is 666430091. The reversal of 666430056 is 650034666.

It can be written as a sum of positive squares in 4 ways, for example, as 616727556 + 49702500 = 24834^2 + 7050^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 666430056.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 59736 + ... + 70008.

Almost surely, 2^666430056 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 666430056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (973666980).

666430056 is an abundant number, since it is smaller than the sum of its proper divisors (1280903904).

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

666430056 is a wasteful number, since it uses less digits than its factorization.

666430056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10355 (or 10348 counting only the distinct ones).

The product of its (nonzero) digits is 77760, while the sum is 36.

The square root of 666430056 is about 25815.3066222348. The cubic root of 666430056 is about 873.4771032790.

The spelling of 666430056 in words is "six hundred sixty-six million, four hundred thirty thousand, fifty-six".