81310509379008 has 2016 divisors, whose sum is σ = 314585713728000. Its totient is φ = 20002187132928.

The previous prime is 81310509378977. The next prime is 81310509379049. The reversal of 81310509379008 is 80097390501318.

81310509379008 is a `hidden beast` number, since 8 + 1 + 3 + 10 + 509 + 37 + 90 + 0 + 8 = 666.

It is a tau number, because it is divible by the number of its divisors (2016).

It is a super-2 number, since 2×81310509379008² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 42504185860 + ... + 42504187772.

Almost surely, 2^{81310509379008} 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 81310509379008, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (157292856864000).

81310509379008 is an abundant number, since it is smaller than the sum of its proper divisors (233275204348992).

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

81310509379008 is a wasteful number, since it uses less digits than its factorization.

81310509379008 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2064 (or 2024 counting only the distinct ones).

The product of its (nonzero) digits is 1632960, while the sum is 54.

The spelling of 81310509379008 in words is "eighty-one trillion, three hundred ten billion, five hundred nine million, three hundred seventy-nine thousand, eight".