81537269760 has 324 divisors, whose sum is σ = 293131515768. Its totient is φ = 21743271936.

The previous prime is 81537269689. The next prime is 81537269819. The reversal of 81537269760 is 6796273518.

It is a Jordan-Polya number, since it can be written as 6! ⋅ (4!)³ ⋅ (2!)¹³.

81537269760 is a `hidden beast` number, since 81 + 537 + 26 + 9 + 7 + 6 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (324).

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

It is a junction number, because it is equal to n+sod(n) for n = 81537269697 and 81537269706.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 16307453950 + ... + 16307453954.

Almost surely, 2^81537269760 is an apocalyptic number.

81537269760 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 81537269760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (146565757884).

81537269760 is an abundant number, since it is smaller than the sum of its proper divisors (211594246008).

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

81537269760 is an frugal number, since it uses more digits than its factorization.

81537269760 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72 (or 10 counting only the distinct ones).

The product of its (nonzero) digits is 3810240, while the sum is 54.

The spelling of 81537269760 in words is "eighty-one billion, five hundred thirty-seven million, two hundred sixty-nine thousand, seven hundred sixty".