81226229760 has 960 divisors, whose sum is σ = 324981296640. Its totient is φ = 19349176320.

The previous prime is 81226229731. The next prime is 81226229779. The reversal of 81226229760 is 6792262218.

81226229760 is a `hidden beast` number, since 8 + 12 + 2 + 622 + 9 + 7 + 6 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (960).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 2620200945 + ... + 2620200975.

It is an arithmetic number, because the mean of its divisors is an integer number (338522184).

Almost surely, 2^81226229760 is an apocalyptic number.

81226229760 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 81226229760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (162490648320).

81226229760 is an abundant number, since it is smaller than the sum of its proper divisors (243755066880).

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

81226229760 is an frugal number, since it uses more digits than its factorization.

81226229760 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 98 (or 54 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 45.

The spelling of 81226229760 in words is "eighty-one billion, two hundred twenty-six million, two hundred twenty-nine thousand, seven hundred sixty".