638887467768 has 64 divisors (see below), whose sum is σ = 1742494273920. Its totient is φ = 193594051200.

The previous prime is 638887467731. The next prime is 638887467787. The reversal of 638887467768 is 867764788836.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 638887467693 and 638887467702.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9653446 + ... + 9719402.

It is an arithmetic number, because the mean of its divisors is an integer number (27226473030).

Almost surely, 2^638887467768 is an apocalyptic number.

It is an amenable number.

638887467768 is an abundant number, since it is smaller than the sum of its proper divisors (1103606806152).

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

638887467768 is a wasteful number, since it uses less digits than its factorization.

638887467768 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 102668 (or 102664 counting only the distinct ones).

The product of its digits is 3641573376, while the sum is 78.

The spelling of 638887467768 in words is "six hundred thirty-eight billion, eight hundred eighty-seven million, four hundred sixty-seven thousand, seven hundred sixty-eight".