81040512512 has 160 divisors (see below), whose sum is σ = 173588336064. Its totient is φ = 37711872000.

The previous prime is 81040512463. The next prime is 81040512533. The reversal of 81040512512 is 21521504018.

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, 72551378 + ... + 72552494.

Almost surely, 2^81040512512 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 81040512512, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (86794168032).

81040512512 is an abundant number, since it is smaller than the sum of its proper divisors (92547823552).

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

81040512512 is a wasteful number, since it uses less digits than its factorization.

81040512512 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1320 (or 1304 counting only the distinct ones).

The product of its (nonzero) digits is 3200, while the sum is 29.

The spelling of 81040512512 in words is "eighty-one billion, forty million, five hundred twelve thousand, five hundred twelve".