81192822896640 has 1536 divisors, whose sum is σ = 322995568896000. Its totient is φ = 16955165638656.

The previous prime is 81192822896593. The next prime is 81192822896683. The reversal of 81192822896640 is 4669822829118.

It is a tau number, because it is divible by the number of its divisors (1536).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 208721909566 + ... + 208721909954.

It is an arithmetic number, because the mean of its divisors is an integer number (210283573500).

Almost surely, 2^{81192822896640} is an apocalyptic number.

81192822896640 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 81192822896640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (161497784448000).

81192822896640 is an abundant number, since it is smaller than the sum of its proper divisors (241802745999360).

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

81192822896640 is a wasteful number, since it uses less digits than its factorization.

81192822896640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1015 (or 995 counting only the distinct ones).

The product of its (nonzero) digits is 47775744, while the sum is 66.

The spelling of 81192822896640 in words is "eighty-one trillion, one hundred ninety-two billion, eight hundred twenty-two million, eight hundred ninety-six thousand, six hundred forty".