81713 has 4 divisors (see below), whose sum is σ = 83748. Its totient is φ = 79680.

The previous prime is 81707. The next prime is 81727. The reversal of 81713 is 31718.

81713 is nontrivially palindromic in base 16.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 31718 = 2 ⋅15859.

It can be written as a sum of positive squares in 2 ways, for example, as 27889 + 53824 = 167^2 + 232^2 .

It is a cyclic number.

It is not a de Polignac number, because 81713 - 2⁶ = 81649 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81703) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 956 + ... + 1037.

It is an arithmetic number, because the mean of its divisors is an integer number (20937).

2⁸¹⁷¹³ is an apocalyptic number.

It is an amenable number.

81713 is a deficient number, since it is larger than the sum of its proper divisors (2035).

81713 is a wasteful number, since it uses less digits than its factorization.

81713 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2034.

The product of its digits is 168, while the sum is 20.

The square root of 81713 is about 285.8548582760. The cubic root of 81713 is about 43.3940699919.

The spelling of 81713 in words is "eighty-one thousand, seven hundred thirteen".