663947701 has 4 divisors (see below), whose sum is σ = 664012672. Its totient is φ = 663882732.

The previous prime is 663947681. The next prime is 663947707. The reversal of 663947701 is 107749366.

663947701 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 663947701 - 2¹⁹ = 663423413 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (663947707) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13431 + ... + 38836.

It is an arithmetic number, because the mean of its divisors is an integer number (166003168).

Almost surely, 2^663947701 is an apocalyptic number.

It is an amenable number.

663947701 is a deficient number, since it is larger than the sum of its proper divisors (64971).

663947701 is a wasteful number, since it uses less digits than its factorization.

663947701 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64970.

The product of its (nonzero) digits is 190512, while the sum is 43.

The square root of 663947701 is about 25767.1826360586. The cubic root of 663947701 is about 872.3912288769.

The spelling of 663947701 in words is "six hundred sixty-three million, nine hundred forty-seven thousand, seven hundred one".