81275173726572 has 216 divisors, whose sum is σ = 247274323732800. Its totient is φ = 22416597245952.

The previous prime is 81275173726559. The next prime is 81275173726583. The reversal of 81275173726572 is 27562737157218.

81275173726572 is a `hidden beast` number, since 8 + 1 + 2 + 7 + 5 + 1 + 7 + 37 + 26 + 572 = 666.

81275173726572 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 282186028 + ... + 282473900.

It is an arithmetic number, because the mean of its divisors is an integer number (1144788535800).

Almost surely, 2^{81275173726572} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81275173726572, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (123637161866400).

81275173726572 is an abundant number, since it is smaller than the sum of its proper divisors (165999150006228).

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

81275173726572 is a wasteful number, since it uses less digits than its factorization.

81275173726572 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 293445 (or 293433 counting only the distinct ones).

The product of its digits is 69148800, while the sum is 63.

The spelling of 81275173726572 in words is "eighty-one trillion, two hundred seventy-five billion, one hundred seventy-three million, seven hundred twenty-six thousand, five hundred seventy-two".