81933 has 8 divisors (see below), whose sum is σ = 112896. Its totient is φ = 52800.

The previous prime is 81931. The next prime is 81937. The reversal of 81933 is 33918.

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

It is not a de Polignac number, because 81933 - 2¹ = 81931 is a prime.

It is a Smith number, since the sum of its digits (24) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

81933 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81931) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 348 + ... + 533.

It is an arithmetic number, because the mean of its divisors is an integer number (14112).

2⁸¹⁹³³ is an apocalyptic number.

It is an amenable number.

81933 is a deficient number, since it is larger than the sum of its proper divisors (30963).

81933 is a wasteful number, since it uses less digits than its factorization.

81933 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 915.

The product of its digits is 648, while the sum is 24.

The square root of 81933 is about 286.2394102845. The cubic root of 81933 is about 43.4329791027.

The spelling of 81933 in words is "eighty-one thousand, nine hundred thirty-three".