638584688634 has 8 divisors (see below), whose sum is σ = 1277169377280. Its totient is φ = 212861562876.

The previous prime is 638584688597. The next prime is 638584688639. The reversal of 638584688634 is 436886485836.

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

638584688634 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (638584688639) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 53215390714 + ... + 53215390725.

It is an arithmetic number, because the mean of its divisors is an integer number (159646172160).

Almost surely, 2^638584688634 is an apocalyptic number.

638584688634 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

638584688634 is a wasteful number, since it uses less digits than its factorization.

638584688634 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106430781444.

The product of its digits is 637009920, while the sum is 69.

The spelling of 638584688634 in words is "six hundred thirty-eight billion, five hundred eighty-four million, six hundred eighty-eight thousand, six hundred thirty-four".