81104667440 has 80 divisors (see below), whose sum is σ = 191379953280. Its totient is φ = 31959982080.

The previous prime is 81104667439. The next prime is 81104667463. The reversal of 81104667440 is 4476640118.

It is a tau number, because it is divible by the number of its divisors (80).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2874200 + ... + 2902280.

It is an arithmetic number, because the mean of its divisors is an integer number (2392249416).

Almost surely, 2^81104667440 is an apocalyptic number.

81104667440 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 81104667440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (95689976640).

81104667440 is an abundant number, since it is smaller than the sum of its proper divisors (110275285840).

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

81104667440 is a wasteful number, since it uses less digits than its factorization.

81104667440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28630 (or 28624 counting only the distinct ones).

The product of its (nonzero) digits is 129024, while the sum is 41.

The spelling of 81104667440 in words is "eighty-one billion, one hundred four million, six hundred sixty-seven thousand, four hundred forty".