81267298560 has 1728 divisors, whose sum is σ = 367331328000. Its totient is φ = 16164126720.

The previous prime is 81267298547. The next prime is 81267298571. The reversal of 81267298560 is 6589276218.

81267298560 is a `hidden beast` number, since 8 + 1 + 2 + 6 + 72 + 9 + 8 + 560 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 81267298497 and 81267298506.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 1377411811 + ... + 1377411869.

It is an arithmetic number, because the mean of its divisors is an integer number (212576000).

Almost surely, 2^81267298560 is an apocalyptic number.

81267298560 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 81267298560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (183665664000).

81267298560 is an abundant number, since it is smaller than the sum of its proper divisors (286064029440).

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

81267298560 is a wasteful number, since it uses less digits than its factorization.

81267298560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 172 (or 155 counting only the distinct ones).

The product of its (nonzero) digits is 2903040, while the sum is 54.

The spelling of 81267298560 in words is "eighty-one billion, two hundred sixty-seven million, two hundred ninety-eight thousand, five hundred sixty".