81559258774713 has 6 divisors (see below), whose sum is σ = 117807818230154. Its totient is φ = 54372839183136.

The previous prime is 81559258774667. The next prime is 81559258774727. The reversal of 81559258774713 is 31747785295518.

81559258774713 is a `hidden beast` number, since 8 + 1 + 5 + 59 + 25 + 87 + 7 + 471 + 3 = 666.

It can be written as a sum of positive squares in only one way, i.e., 81557750850489 + 1507924224 = 9030933^2 + 38832^2 .

It is not a de Polignac number, because 81559258774713 - 2³⁷ = 81421819821241 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81559258734713) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4531069931920 + ... + 4531069931937.

Almost surely, 2^{81559258774713} is an apocalyptic number.

It is an amenable number.

81559258774713 is a deficient number, since it is larger than the sum of its proper divisors (36248559455441).

81559258774713 is a wasteful number, since it uses less digits than its factorization.

81559258774713 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9062139863863 (or 9062139863860 counting only the distinct ones).

The product of its digits is 592704000, while the sum is 72.

The spelling of 81559258774713 in words is "eighty-one trillion, five hundred fifty-nine billion, two hundred fifty-eight million, seven hundred seventy-four thousand, seven hundred thirteen".