638364066643 has 8 divisors (see below), whose sum is σ = 652628512368. Its totient is φ = 624181837344.

The previous prime is 638364066631. The next prime is 638364066661. The reversal of 638364066643 is 346660463836.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-638364066643 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (638364066143) 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 7 ways as a sum of consecutive naturals, for example, 20538405 + ... + 20569462.

It is an arithmetic number, because the mean of its divisors is an integer number (81578564046).

Almost surely, 2^638364066643 is an apocalyptic number.

638364066643 is a deficient number, since it is larger than the sum of its proper divisors (14264445725).

638364066643 is a wasteful number, since it uses less digits than its factorization.

638364066643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41108213.

The product of its (nonzero) digits is 26873856, while the sum is 55.

The spelling of 638364066643 in words is "six hundred thirty-eight billion, three hundred sixty-four million, sixty-six thousand, six hundred forty-three".