81031104000 has 2400 divisors, whose sum is σ = 396244236960. Its totient is φ = 16257024000.

The previous prime is 81031103999. The next prime is 81031104013. The reversal of 81031104000 is 40113018.

It is a tau number, because it is divible by the number of its divisors (2400).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 239 ways as a sum of consecutive naturals, for example, 2794175986 + ... + 2794176014.

Almost surely, 2^81031104000 is an apocalyptic number.

81031104000 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 81031104000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (198122118480).

81031104000 is an abundant number, since it is smaller than the sum of its proper divisors (315213132960).

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

81031104000 is a wasteful number, since it uses less digits than its factorization.

81031104000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99 (or 57 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 18.

Adding to 81031104000 its reverse (40113018), we get a palindrome (81071217018).

The spelling of 81031104000 in words is "eighty-one billion, thirty-one million, one hundred four thousand".