638580738260 has 72 divisors (see below), whose sum is σ = 1426310111520. Its totient is φ = 239492422656.

The previous prime is 638580738233. The next prime is 638580738307. The reversal of 638580738260 is 62837085836.

It is a junction number, because it is equal to n+sod(n) for n = 638580738196 and 638580738205.

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 23 ways as a sum of consecutive naturals, for example, 3486119 + ... + 3664721.

It is an arithmetic number, because the mean of its divisors is an integer number (19809862660).

Almost surely, 2^638580738260 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 638580738260, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (713155055760).

638580738260 is an abundant number, since it is smaller than the sum of its proper divisors (787729373260).

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

638580738260 is a wasteful number, since it uses less digits than its factorization.

638580738260 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 178825 (or 178726 counting only the distinct ones).

The product of its (nonzero) digits is 11612160, while the sum is 56.

The spelling of 638580738260 in words is "six hundred thirty-eight billion, five hundred eighty million, seven hundred thirty-eight thousand, two hundred sixty".