81318 has 8 divisors (see below), whose sum is σ = 162648. Its totient is φ = 27104.

The previous prime is 81307. The next prime is 81331.

It is a happy number.

81318 is nontrivially palindromic in base 10.

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

81318 is an admirable number.

It is a super-2 number, since 2×81318² = 13225234248, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 81294 and 81303.

It is a congruent number.

It is an unprimeable number.

81318 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6771 + ... + 6782.

It is an arithmetic number, because the mean of its divisors is an integer number (20331).

2⁸¹³¹⁸ is an apocalyptic number.

81318 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (81324).

81318 is a wasteful number, since it uses less digits than its factorization.

81318 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13558.

The product of its digits is 192, while the sum is 21.

The square root of 81318 is about 285.1631112188. The cubic root of 81318 is about 43.3240348227.

It can be divided in two parts, 8 and 1318, that added together give a triangular number (1326 = T₅₁).

The spelling of 81318 in words is "eighty-one thousand, three hundred eighteen".