81706237634560 has 576 divisors, whose sum is σ = 252292290606720. Its totient is φ = 25108070400000.

The previous prime is 81706237634551. The next prime is 81706237634603. The reversal of 81706237634560 is 6543673260718.

It is a junction number, because it is equal to n+sod(n) for n = 81706237634495 and 81706237634504.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 391770310 + ... + 391978810.

It is an arithmetic number, because the mean of its divisors is an integer number (438007448970).

Almost surely, 2^{81706237634560} is an apocalyptic number.

81706237634560 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 81706237634560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (126146145303360).

81706237634560 is an abundant number, since it is smaller than the sum of its proper divisors (170586052972160).

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

81706237634560 is a wasteful number, since it uses less digits than its factorization.

81706237634560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 208624 (or 208597 counting only the distinct ones).

The product of its (nonzero) digits is 30481920, while the sum is 58.

The spelling of 81706237634560 in words is "eighty-one trillion, seven hundred six billion, two hundred thirty-seven million, six hundred thirty-four thousand, five hundred sixty".