81065014464 has 224 divisors, whose sum is σ = 249936975360. Its totient is φ = 22708887552.

The previous prime is 81065014453. The next prime is 81065014489. The reversal of 81065014464 is 46441056018.

It is a tau number, because it is divible by the number of its divisors (224).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 36237154 + ... + 36239390.

Almost surely, 2^81065014464 is an apocalyptic number.

81065014464 is a gapful number since it is divisible by the number (84) 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 81065014464, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (124968487680).

81065014464 is an abundant number, since it is smaller than the sum of its proper divisors (168871960896).

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

81065014464 is a wasteful number, since it uses less digits than its factorization.

81065014464 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2775 (or 2765 counting only the distinct ones).

The product of its (nonzero) digits is 92160, while the sum is 39.

The spelling of 81065014464 in words is "eighty-one billion, sixty-five million, fourteen thousand, four hundred sixty-four".