81111111111118 has 32 divisors (see below), whose sum is σ = 136126580002560. Its totient is φ = 35926578456000.

The previous prime is 81111111111109. The next prime is 81111111111127.

81111111111118 is nontrivially palindromic in base 10.

It is an interprime number because it is at equal distance from previous prime (81111111111109) and next prime (81111111111127).

81111111111118 is a strobogrammatic number because it is the same when read upside-down.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 52832988 + ... + 54346543.

It is an arithmetic number, because the mean of its divisors is an integer number (4253955625080).

Almost surely, 2^{81111111111118} is an apocalyptic number.

81111111111118 is a deficient number, since it is larger than the sum of its proper divisors (55015468891442).

81111111111118 is a wasteful number, since it uses less digits than its factorization.

81111111111118 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107180424.

The product of its digits is 64, while the sum is 28.

It can be divided in two parts, 8111111 and 1111118, that added together give a palindrome (9222229).

The spelling of 81111111111118 in words is "eighty-one trillion, one hundred eleven billion, one hundred eleven million, one hundred eleven thousand, one hundred eighteen".