81263054407680 has 2688 divisors, whose sum is σ = 325766310105600. Its totient is φ = 19352361369600.

The previous prime is 81263054407627. The next prime is 81263054407699. The reversal of 81263054407680 is 8670445036218.

It is a happy number.

81263054407680 is a `hidden beast` number, since 8 + 1 + 2 + 6 + 30 + 544 + 0 + 7 + 68 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 223 ways as a sum of consecutive naturals, for example, 261295994725 + ... + 261295995035.

It is an arithmetic number, because the mean of its divisors is an integer number (121192823700).

Almost surely, 2^{81263054407680} is an apocalyptic number.

81263054407680 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 81263054407680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (162883155052800).

81263054407680 is an abundant number, since it is smaller than the sum of its proper divisors (244503255697920).

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

81263054407680 is a wasteful number, since it uses less digits than its factorization.

81263054407680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 473 (or 438 counting only the distinct ones).

The product of its (nonzero) digits is 7741440, while the sum is 54.

The spelling of 81263054407680 in words is "eighty-one trillion, two hundred sixty-three billion, fifty-four million, four hundred seven thousand, six hundred eighty".