638353648782 has 12 divisors (see below), whose sum is σ = 1383099572400. Its totient is φ = 212784549588.

The previous prime is 638353648753. The next prime is 638353648783. The reversal of 638353648782 is 287846353836.

It is a Smith number, since the sum of its digits (63) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638353648783) 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 5 ways as a sum of consecutive naturals, for example, 17732045782 + ... + 17732045817.

It is an arithmetic number, because the mean of its divisors is an integer number (115258297700).

Almost surely, 2^638353648782 is an apocalyptic number.

638353648782 is an abundant number, since it is smaller than the sum of its proper divisors (744745923618).

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

638353648782 is a wasteful number, since it uses less digits than its factorization.

638353648782 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35464091607 (or 35464091604 counting only the distinct ones).

The product of its digits is 139345920, while the sum is 63.

The spelling of 638353648782 in words is "six hundred thirty-eight billion, three hundred fifty-three million, six hundred forty-eight thousand, seven hundred eighty-two".