It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 18527 = 97 ⋅191.
It is a cyclic number.
It is an Ulam number.
It is an alternating number because its digits alternate between odd and even.
It is a Duffinian number.
It is a plaindrome in base 15.
It is a congruent number.
It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 72581.
272581 is an apocalyptic number.
72581 is the 191-st centered square number.
It is an amenable number.
72581 is a wasteful number, since it uses less digits than its factorization.
72581 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 582.
The square root of 72581 is about 269.4086115921. The cubic root of 72581 is about 41.7132776164.
The spelling of 72581 in words is "seventy-two thousand, five hundred eighty-one".