81593115459 has 16 divisors (see below), whose sum is σ = 117869127552. Its totient is φ = 50005081728.

The previous prime is 81593115437. The next prime is 81593115491. The reversal of 81593115459 is 95451139518.

It is a happy number.

It is not a de Polignac number, because 81593115459 - 2⁵ = 81593115427 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is not an unprimeable number, because it can be changed into a prime (81593115259) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18600889 + ... + 18605274.

It is an arithmetic number, because the mean of its divisors is an integer number (7366820472).

Almost surely, 2^81593115459 is an apocalyptic number.

81593115459 is a deficient number, since it is larger than the sum of its proper divisors (36276012093).

81593115459 is a wasteful number, since it uses less digits than its factorization.

81593115459 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37206226.

The product of its digits is 972000, while the sum is 51.

The spelling of 81593115459 in words is "eighty-one billion, five hundred ninety-three million, one hundred fifteen thousand, four hundred fifty-nine".