981256661056000 has 1400 divisors, whose sum is σ = 3013214569727076. Its totient is φ = 318723968102400.

The previous prime is 981256661055991. The next prime is 981256661056033. The reversal of 981256661056000 is 650166652189.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It can be written as a sum of positive squares in 2 ways, for example, as 663329502873856 + 317927158182144 = 25755184^2 + 17830512^2 .

It is a tau number, because it is divible by the number of its divisors (1400).

It is a taxicab number since it can be written as a sum of two cubes in more than one way. Here 981256661056000 = 35112³ + 97888³ = 55860³ + 93100³.

It is an unprimeable number.

It is a polite number, since it can be written in 139 ways as a sum of consecutive naturals, for example, 51645087423991 + ... + 51645087424009.

Almost surely, 2^{981256661056000} 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 981256661056000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1506607284863538).

981256661056000 is an abundant number, since it is smaller than the sum of its proper divisors (2031957908671076).

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

981256661056000 is an frugal number, since it uses more digits than its factorization.

981256661056000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 151 (or 33 counting only the distinct ones).

The product of its (nonzero) digits is 4665600, while the sum is 55.

The spelling of 981256661056000 in words is "nine hundred eighty-one trillion, two hundred fifty-six billion, six hundred sixty-one million, fifty-six thousand".