81793 has 4 divisors (see below), whose sum is σ = 82368. Its totient is φ = 81220.

The previous prime is 81773. The next prime is 81799. The reversal of 81793 is 39718.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 81793 - 2⁵ = 81761 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81799) 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, 108 + ... + 418.

It is an arithmetic number, because the mean of its divisors is an integer number (20592).

2⁸¹⁷⁹³ is an apocalyptic number.

It is an amenable number.

81793 is a deficient number, since it is larger than the sum of its proper divisors (575).

81793 is a wasteful number, since it uses less digits than its factorization.

81793 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 574.

The product of its digits is 1512, while the sum is 28.

The square root of 81793 is about 285.9947551967. The cubic root of 81793 is about 43.4082268306.

The spelling of 81793 in words is "eighty-one thousand, seven hundred ninety-three".