7989121487256 has 256 divisors, whose sum is σ = 24667324416000. Its totient is φ = 2099709927936.

The previous prime is 7989121487213. The next prime is 7989121487261. The reversal of 7989121487256 is 6527841219897.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1170220915 + ... + 1170227741.

It is an arithmetic number, because the mean of its divisors is an integer number (96356736000).

Almost surely, 2^{7989121487256} 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 7989121487256, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (12333662208000).

7989121487256 is an abundant number, since it is smaller than the sum of its proper divisors (16678202928744).

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

7989121487256 is a wasteful number, since it uses less digits than its factorization.

7989121487256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8638 (or 8634 counting only the distinct ones).

The product of its digits is 121927680, while the sum is 69.

The spelling of 7989121487256 in words is "seven trillion, nine hundred eighty-nine billion, one hundred twenty-one million, four hundred eighty-seven thousand, two hundred fifty-six".