8621221289408 has 112 divisors (see below), whose sum is σ = 21058733217984. Its totient is φ = 3410097684480.

The previous prime is 8621221289333. The next prime is 8621221289449. The reversal of 8621221289408 is 8049821221268.

It is a tau number, because it is divible by the number of its divisors (112).

It is a self number, because there is not a number n which added to its sum of digits gives 8621221289408.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 41368766 + ... + 41576642.

It is an arithmetic number, because the mean of its divisors is an integer number (188024403732).

Almost surely, 2^{8621221289408} 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 8621221289408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10529366608992).

8621221289408 is an abundant number, since it is smaller than the sum of its proper divisors (12437511928576).

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

8621221289408 is a wasteful number, since it uses less digits than its factorization.

8621221289408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 215030 (or 215020 counting only the distinct ones).

The product of its (nonzero) digits is 1769472, while the sum is 53.

The spelling of 8621221289408 in words is "eight trillion, six hundred twenty-one billion, two hundred twenty-one million, two hundred eighty-nine thousand, four hundred eight".