81133298792 has 192 divisors, whose sum is σ = 193751974080. Its totient is φ = 31565334528.

The previous prime is 81133298773. The next prime is 81133298801. The reversal of 81133298792 is 29789233118.

It is a happy number.

It is a super-2 number, since 2×81133298792² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 183144923 + ... + 183145365.

It is an arithmetic number, because the mean of its divisors is an integer number (1009124865).

Almost surely, 2^81133298792 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81133298792, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (96875987040).

81133298792 is an abundant number, since it is smaller than the sum of its proper divisors (112618675288).

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

81133298792 is a wasteful number, since it uses less digits than its factorization.

81133298792 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 992 (or 981 counting only the distinct ones).

The product of its digits is 1306368, while the sum is 53.

The spelling of 81133298792 in words is "eighty-one billion, one hundred thirty-three million, two hundred ninety-eight thousand, seven hundred ninety-two".