81673 has 8 divisors (see below), whose sum is σ = 88128. Its totient is φ = 75504.

The previous prime is 81671. The next prime is 81677. The reversal of 81673 is 37618.

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

It is a cyclic number.

It is not a de Polignac number, because 81673 - 2¹ = 81671 is a prime.

It is a Duffinian 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 7 ways as a sum of consecutive naturals, for example, 1186 + ... + 1252.

It is an arithmetic number, because the mean of its divisors is an integer number (11016).

2⁸¹⁶⁷³ is an apocalyptic number.

It is an amenable number.

81673 is a deficient number, since it is larger than the sum of its proper divisors (6455).

81673 is a wasteful number, since it uses less digits than its factorization.

81673 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 143.

The product of its digits is 1008, while the sum is 25.

The square root of 81673 is about 285.7848841349. The cubic root of 81673 is about 43.3869881073.

It can be divided in two parts, 8 and 1673, that added together give a square (1681 = 41²).

The spelling of 81673 in words is "eighty-one thousand, six hundred seventy-three".