663245856 has 144 divisors (see below), whose sum is σ = 2321452224. Its totient is φ = 174915072.

The previous prime is 663245819. The next prime is 663245887. The reversal of 663245856 is 658542366.

663245856 is a `hidden beast` number, since 6 + 63 + 2 + 4 + 585 + 6 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

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, 13555 + ... + 38861.

It is an arithmetic number, because the mean of its divisors is an integer number (16121196).

Almost surely, 2^663245856 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 663245856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1160726112).

663245856 is an abundant number, since it is smaller than the sum of its proper divisors (1658206368).

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

663245856 is a wasteful number, since it uses less digits than its factorization.

663245856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25343 (or 25332 counting only the distinct ones).

The product of its digits is 1036800, while the sum is 45.

The square root of 663245856 is about 25753.5600645814. The cubic root of 663245856 is about 872.0837250922.

The spelling of 663245856 in words is "six hundred sixty-three million, two hundred forty-five thousand, eight hundred fifty-six".