663656945 has 16 divisors (see below), whose sum is σ = 915749760. Its totient is φ = 452283264.

The previous prime is 663656921. The next prime is 663656963. The reversal of 663656945 is 549656366.

It is a cyclic number.

It is not a de Polignac number, because 663656945 - 2⁸ = 663656689 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 663656893 and 663656902.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 52460 + ... + 63869.

It is an arithmetic number, because the mean of its divisors is an integer number (57234360).

Almost surely, 2^663656945 is an apocalyptic number.

It is an amenable number.

663656945 is a deficient number, since it is larger than the sum of its proper divisors (252092815).

663656945 is a wasteful number, since it uses less digits than its factorization.

663656945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 116504.

The product of its digits is 3499200, while the sum is 50.

The square root of 663656945 is about 25761.5400354870. The cubic root of 663656945 is about 872.2638644177.

The spelling of 663656945 in words is "six hundred sixty-three million, six hundred fifty-six thousand, nine hundred forty-five".