81241581717 has 8 divisors (see below), whose sum is σ = 120357898880. Its totient is φ = 54161054460.

The previous prime is 81241581689. The next prime is 81241581767. The reversal of 81241581717 is 71718514218.

81241581717 is a `hidden beast` number, since 8 + 12 + 41 + 581 + 7 + 17 = 666.

It is not a de Polignac number, because 81241581717 - 2⁸ = 81241581461 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81241581767) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1504473709 + ... + 1504473762.

It is an arithmetic number, because the mean of its divisors is an integer number (15044737360).

Almost surely, 2^81241581717 is an apocalyptic number.

It is an amenable number.

81241581717 is a deficient number, since it is larger than the sum of its proper divisors (39116317163).

81241581717 is a wasteful number, since it uses less digits than its factorization.

81241581717 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3008947480 (or 3008947474 counting only the distinct ones).

The product of its digits is 125440, while the sum is 45.

The spelling of 81241581717 in words is "eighty-one billion, two hundred forty-one million, five hundred eighty-one thousand, seven hundred seventeen".