81234043218 has 12 divisors (see below), whose sum is σ = 176007093678. Its totient is φ = 27078014400.

The previous prime is 81234043141. The next prime is 81234043273.

It is a happy number.

81234043218 is nontrivially palindromic in base 10.

It can be written as a sum of positive squares in only one way, i.e., 79542613089 + 1691430129 = 282033^2 + 41127^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2256501183 + ... + 2256501218.

Almost surely, 2^81234043218 is an apocalyptic number.

81234043218 is an abundant number, since it is smaller than the sum of its proper divisors (94773050460).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81234043218 is a wasteful number, since it uses less digits than its factorization.

81234043218 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4513002409 (or 4513002406 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 36.

It can be divided in two parts, 812340 and 43218, that added together give a palindrome (855558).

The spelling of 81234043218 in words is "eighty-one billion, two hundred thirty-four million, forty-three thousand, two hundred eighteen".