663628320 has 144 divisors (see below), whose sum is σ = 2397933720. Its totient is φ = 166551552.

The previous prime is 663628309. The next prime is 663628349. The reversal of 663628320 is 23826366.

663628320 is a `hidden beast` number, since 6 + 6 + 3 + 628 + 3 + 20 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 554885136 + 108743184 = 23556^2 + 10428^2 .

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

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

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, 10926 + ... + 38034.

Almost surely, 2^663628320 is an apocalyptic number.

663628320 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 663628320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1198966860).

663628320 is an abundant number, since it is smaller than the sum of its proper divisors (1734305400).

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

663628320 is a wasteful number, since it uses less digits than its factorization.

663628320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27147 (or 27136 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 36.

The square root of 663628320 is about 25760.9844532386. The cubic root of 663628320 is about 872.2513233439.

The spelling of 663628320 in words is "six hundred sixty-three million, six hundred twenty-eight thousand, three hundred twenty".