81678 has 8 divisors (see below), whose sum is σ = 163368. Its totient is φ = 27224.

The previous prime is 81677. The next prime is 81689. The reversal of 81678 is 87618.

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

81678 is an admirable number.

It is an alternating number because its digits alternate between even and odd.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81671) 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, 6801 + ... + 6812.

It is an arithmetic number, because the mean of its divisors is an integer number (20421).

2⁸¹⁶⁷⁸ is an apocalyptic number.

81678 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 (81684).

81678 is a wasteful number, since it uses less digits than its factorization.

81678 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13618.

The product of its digits is 2688, while the sum is 30.

The square root of 81678 is about 285.7936318395. The cubic root of 81678 is about 43.3878734693.

The spelling of 81678 in words is "eighty-one thousand, six hundred seventy-eight".