81711360000 has 720 divisors, whose sum is σ = 303841317780. Its totient is φ = 21135360000.

The previous prime is 81711359999. The next prime is 81711360007. The reversal of 81711360000 is 6311718.

It can be written as a sum of positive squares in 10 ways, for example, as 8370054144 + 73341305856 = 91488^2 + 270816^2 .

It is a tau number, because it is divible by the number of its divisors (720).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81711360007) by changing a digit.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 472319914 + ... + 472320086.

Almost surely, 2^81711360000 is an apocalyptic number.

81711360000 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81711360000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (151920658890).

81711360000 is an abundant number, since it is smaller than the sum of its proper divisors (222129957780).

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

81711360000 is a wasteful number, since it uses less digits than its factorization.

81711360000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 262 (or 224 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 27.

Adding to 81711360000 its reverse (6311718), we get a palindrome (81717671718).

The spelling of 81711360000 in words is "eighty-one billion, seven hundred eleven million, three hundred sixty thousand".