81125415822 has 96 divisors (see below), whose sum is σ = 184400244000. Its totient is φ = 23757338880.

The previous prime is 81125415809. The next prime is 81125415829. The reversal of 81125415822 is 22851452118.

It is a super-4 number, since 4×81125415822⁴ (a number of 45 digits) contains 4444 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81125415829) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 3992304 + ... + 4012572.

It is an arithmetic number, because the mean of its divisors is an integer number (1920835875).

Almost surely, 2^81125415822 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81125415822, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (92200122000).

81125415822 is an abundant number, since it is smaller than the sum of its proper divisors (103274828178).

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

81125415822 is a wasteful number, since it uses less digits than its factorization.

81125415822 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20482 (or 20471 counting only the distinct ones).

The product of its digits is 51200, while the sum is 39.

The spelling of 81125415822 in words is "eighty-one billion, one hundred twenty-five million, four hundred fifteen thousand, eight hundred twenty-two".