663709243679 has 4 divisors (see below), whose sum is σ = 681647331384. Its totient is φ = 645771155976.

The previous prime is 663709243667. The next prime is 663709243733. The reversal of 663709243679 is 976342907366.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 663709243679 - 2⁴ = 663709243663 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 (663709243279) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8969043797 + ... + 8969043870.

It is an arithmetic number, because the mean of its divisors is an integer number (170411832846).

Almost surely, 2^663709243679 is an apocalyptic number.

663709243679 is a deficient number, since it is larger than the sum of its proper divisors (17938087705).

663709243679 is a wasteful number, since it uses less digits than its factorization.

663709243679 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17938087704.

The product of its (nonzero) digits is 61725888, while the sum is 62.

The spelling of 663709243679 in words is "six hundred sixty-three billion, seven hundred nine million, two hundred forty-three thousand, six hundred seventy-nine".