638171619696 has 480 divisors, whose sum is σ = 2118344417280. Its totient is φ = 177607987200.

The previous prime is 638171619671. The next prime is 638171619707. The reversal of 638171619696 is 696916171836.

638171619696 is a `hidden beast` number, since 6 + 3 + 8 + 1 + 7 + 1 + 619 + 6 + 9 + 6 = 666.

It is a congruent number.

It is an unprimeable number.

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 95 ways as a sum of consecutive naturals, for example, 68534881 + ... + 68544191.

It is an arithmetic number, because the mean of its divisors is an integer number (4413217536).

Almost surely, 2^638171619696 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 638171619696, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1059172208640).

638171619696 is an abundant number, since it is smaller than the sum of its proper divisors (1480172797584).

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

638171619696 is a wasteful number, since it uses less digits than its factorization.

638171619696 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9445 (or 9436 counting only the distinct ones).

The product of its digits is 17635968, while the sum is 63.

The spelling of 638171619696 in words is "six hundred thirty-eight billion, one hundred seventy-one million, six hundred nineteen thousand, six hundred ninety-six".