8638721169408 has 384 divisors, whose sum is σ = 29385641376000. Its totient is φ = 2480012328960.

The previous prime is 8638721169383. The next prime is 8638721169443. The reversal of 8638721169408 is 8049611278368.

8638721169408 is a `hidden beast` number, since 8 + 6 + 3 + 8 + 7 + 211 + 6 + 9 + 408 = 666.

It is a tau number, because it is divible by the number of its divisors (384).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 11183116 + ... + 11930612.

It is an arithmetic number, because the mean of its divisors is an integer number (76525107750).

Almost surely, 2^{8638721169408} is an apocalyptic number.

8638721169408 is a gapful number since it is divisible by the number (88) 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 8638721169408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14692820688000).

8638721169408 is an abundant number, since it is smaller than the sum of its proper divisors (20746920206592).

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

8638721169408 is a wasteful number, since it uses less digits than its factorization.

8638721169408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 747558 (or 747532 counting only the distinct ones).

The product of its (nonzero) digits is 27869184, while the sum is 63.

The spelling of 8638721169408 in words is "eight trillion, six hundred thirty-eight billion, seven hundred twenty-one million, one hundred sixty-nine thousand, four hundred eight".