638351568438 has 8 divisors (see below), whose sum is σ = 1276703136888. Its totient is φ = 212783856144.

The previous prime is 638351568359. The next prime is 638351568443. The reversal of 638351568438 is 834865153836.

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

638351568438 is an admirable number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 53195964031 + ... + 53195964042.

It is an arithmetic number, because the mean of its divisors is an integer number (159587892111).

Almost surely, 2^638351568438 is an apocalyptic number.

638351568438 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.

638351568438 is a wasteful number, since it uses less digits than its factorization.

638351568438 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106391928078.

The product of its digits is 49766400, while the sum is 60.

The spelling of 638351568438 in words is "six hundred thirty-eight billion, three hundred fifty-one million, five hundred sixty-eight thousand, four hundred thirty-eight".