81287078218 has 8 divisors (see below), whose sum is σ = 122890701312. Its totient is φ = 40323511116.

The previous prime is 81287078207. The next prime is 81287078219.

81287078218 is nontrivially palindromic in base 10.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (81287078219) 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 3 ways as a sum of consecutive naturals, for example, 160013680 + ... + 160014187.

It is an arithmetic number, because the mean of its divisors is an integer number (15361337664).

Almost surely, 2^81287078218 is an apocalyptic number.

81287078218 is a deficient number, since it is larger than the sum of its proper divisors (41603623094).

81287078218 is a wasteful number, since it uses less digits than its factorization.

81287078218 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 320027996.

The product of its (nonzero) digits is 802816, while the sum is 52.

The spelling of 81287078218 in words is "eighty-one billion, two hundred eighty-seven million, seventy-eight thousand, two hundred eighteen".