638181466560 has 1344 divisors, whose sum is σ = 2598446822400. Its totient is φ = 142132838400.

The previous prime is 638181466537. The next prime is 638181466589. The reversal of 638181466560 is 65664181836.

638181466560 is a `hidden beast` number, since 6 + 3 + 8 + 1 + 8 + 14 + 66 + 560 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 638181466497 and 638181466506.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 4658258812 + ... + 4658258948.

Almost surely, 2^638181466560 is an apocalyptic number.

638181466560 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 638181466560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1299223411200).

638181466560 is an abundant number, since it is smaller than the sum of its proper divisors (1960265355840).

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

638181466560 is a wasteful number, since it uses less digits than its factorization.

638181466560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 370 (or 357 counting only the distinct ones).

The product of its (nonzero) digits is 4976640, while the sum is 54.

The spelling of 638181466560 in words is "six hundred thirty-eight billion, one hundred eighty-one million, four hundred sixty-six thousand, five hundred sixty".