81583 has 4 divisors (see below), whose sum is σ = 86400. Its totient is φ = 76768.

The previous prime is 81569. The next prime is 81611. The reversal of 81583 is 38518.

81583 is an esthetic number in base 7, because in such base its adjacent digits differ by 1.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 38518 = 2 ⋅19259.

It is a cyclic number.

It is not a de Polignac number, because 81583 - 2⁵ = 81551 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81533) 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, 2383 + ... + 2416.

It is an arithmetic number, because the mean of its divisors is an integer number (21600).

2⁸¹⁵⁸³ is an apocalyptic number.

81583 is a deficient number, since it is larger than the sum of its proper divisors (4817).

81583 is a wasteful number, since it uses less digits than its factorization.

81583 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4816.

The product of its digits is 960, while the sum is 25.

The square root of 81583 is about 285.6273796400. The cubic root of 81583 is about 43.3710454085.

It can be divided in two parts, 815 and 83, that added together give a palindrome (898).

The spelling of 81583 in words is "eighty-one thousand, five hundred eighty-three".