81708 has 24 divisors (see below), whose sum is σ = 208320. Its totient is φ = 24720.

The previous prime is 81707. The next prime is 81727. The reversal of 81708 is 80718.

It is not an unprimeable number, because it can be changed into a prime (81701) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 178 + ... + 441.

It is an arithmetic number, because the mean of its divisors is an integer number (8680).

2⁸¹⁷⁰⁸ is an apocalyptic number.

It is an amenable number.

81708 is an abundant number, since it is smaller than the sum of its proper divisors (126612).

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 (104160).

81708 is a wasteful number, since it uses less digits than its factorization.

81708 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 637 (or 635 counting only the distinct ones).

The product of its (nonzero) digits is 448, while the sum is 24.

The square root of 81708 is about 285.8461124451. The cubic root of 81708 is about 43.3931848827.

Subtracting from 81708 its reverse (80718), we obtain a triangular number (990 = T₄₄).

The spelling of 81708 in words is "eighty-one thousand, seven hundred eight".