81340 has 36 divisors (see below), whose sum is σ = 201096. Its totient is φ = 27552.

The previous prime is 81331. The next prime is 81343. The reversal of 81340 is 4318.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81343) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 939 + ... + 1021.

It is an arithmetic number, because the mean of its divisors is an integer number (5586).

2⁸¹³⁴⁰ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (100548).

81340 is an abundant number, since it is smaller than the sum of its proper divisors (119756).

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

81340 is a wasteful number, since it uses less digits than its factorization.

81340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106 (or 97 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 16.

The square root of 81340 is about 285.2016830245. The cubic root of 81340 is about 43.3279414725.

Adding to 81340 its reverse (4318), we get a palindrome (85658).

The spelling of 81340 in words is "eighty-one thousand, three hundred forty".