81518318 has 16 divisors (see below), whose sum is σ = 139898880. Its totient is φ = 34898136.

The previous prime is 81518317. The next prime is 81518323. The reversal of 81518318 is 81381518.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81518317) 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 7 ways as a sum of consecutive naturals, for example, 12803 + ... + 18081.

It is an arithmetic number, because the mean of its divisors is an integer number (8743680).

Almost surely, 2^81518318 is an apocalyptic number.

81518318 is a deficient number, since it is larger than the sum of its proper divisors (58380562).

81518318 is a wasteful number, since it uses less digits than its factorization.

81518318 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6391.

The product of its digits is 7680, while the sum is 35.

The square root of 81518318 is about 9028.7495258203. The cubic root of 81518318 is about 433.5958032516.

The spelling of 81518318 in words is "eighty-one million, five hundred eighteen thousand, three hundred eighteen".