81700 has 36 divisors (see below), whose sum is σ = 190960. Its totient is φ = 30240.

The previous prime is 81689. The next prime is 81701. The reversal of 81700 is 718.

It is an Ulam number.

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 11 ways as a sum of consecutive naturals, for example, 1879 + ... + 1921.

2⁸¹⁷⁰⁰ 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 81700, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (95480).

81700 is an abundant number, since it is smaller than the sum of its proper divisors (109260).

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

81700 is a wasteful number, since it uses less digits than its factorization.

81700 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76 (or 69 counting only the distinct ones).

The product of its (nonzero) digits is 56, while the sum is 16.

The square root of 81700 is about 285.8321185591. The cubic root of 81700 is about 43.3917686329.

The spelling of 81700 in words is "eighty-one thousand, seven hundred".