81017071018 has 16 divisors (see below), whose sum is σ = 132169513896. Its totient is φ = 37022270400.

The previous prime is 81017071007. The next prime is 81017071021.

It is a happy number.

81017071018 is nontrivially palindromic in base 10.

It can be written as a sum of positive squares in 4 ways, for example, as 63959927409 + 17057143609 = 252903^2 + 130603^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15423321 + ... + 15428572.

Almost surely, 2^81017071018 is an apocalyptic number.

81017071018 is a deficient number, since it is larger than the sum of its proper divisors (51152442878).

81017071018 is a wasteful number, since it uses less digits than its factorization.

81017071018 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30852009.

The product of its (nonzero) digits is 3136, while the sum is 34.

It can be divided in two parts, 810170 and 71018, that added together give a palindrome (881188).

The spelling of 81017071018 in words is "eighty-one billion, seventeen million, seventy-one thousand, eighteen".