81159068193 has 16 divisors (see below), whose sum is σ = 125767080960. Its totient is φ = 45590565456.

The previous prime is 81159068191. The next prime is 81159068201. The reversal of 81159068193 is 39186095118.

It is not a de Polignac number, because 81159068193 - 2¹ = 81159068191 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81159068191) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 32750605 + ... + 32753082.

It is an arithmetic number, because the mean of its divisors is an integer number (7860442560).

Almost surely, 2^81159068193 is an apocalyptic number.

It is an amenable number.

81159068193 is a deficient number, since it is larger than the sum of its proper divisors (44608012767).

81159068193 is a wasteful number, since it uses less digits than its factorization.

81159068193 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65503756.

The product of its (nonzero) digits is 466560, while the sum is 51.

The spelling of 81159068193 in words is "eighty-one billion, one hundred fifty-nine million, sixty-eight thousand, one hundred ninety-three".