81641063112 has 128 divisors (see below), whose sum is σ = 238427504640. Its totient is φ = 22810141440.

The previous prime is 81641063099. The next prime is 81641063113. The reversal of 81641063112 is 21136014618.

It is not an unprimeable number, because it can be changed into a prime (81641063113) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 10900633 + ... + 10908119.

It is an arithmetic number, because the mean of its divisors is an integer number (1862714880).

Almost surely, 2^81641063112 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 81641063112, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (119213752320).

81641063112 is an abundant number, since it is smaller than the sum of its proper divisors (156786441528).

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

81641063112 is a wasteful number, since it uses less digits than its factorization.

81641063112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8931 (or 8927 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 33.

The spelling of 81641063112 in words is "eighty-one billion, six hundred forty-one million, sixty-three thousand, one hundred twelve".