665163556 has 18 divisors (see below), whose sum is σ = 1236538898. Its totient is φ = 313017600.

The previous prime is 665163553. The next prime is 665163589. The reversal of 665163556 is 655361566.

665163556 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 3 ways, for example, as 422302500 + 242861056 = 20550^2 + 15584^2 .

It is not an unprimeable number, because it can be changed into a prime (665163553) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 286545 + ... + 288856.

Almost surely, 2^665163556 is an apocalyptic number.

It is an amenable number.

665163556 is a deficient number, since it is larger than the sum of its proper divisors (571375342).

665163556 is a wasteful number, since it uses less digits than its factorization.

665163556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 575439 (or 575420 counting only the distinct ones).

The product of its digits is 486000, while the sum is 43.

The square root of 665163556 is about 25790.7649363101. The cubic root of 665163556 is about 872.9234266307.

It can be divided in two parts, 6651 and 63556, that added together give a palindrome (70207).

The spelling of 665163556 in words is "six hundred sixty-five million, one hundred sixty-three thousand, five hundred fifty-six".