81241 has 4 divisors (see below), whose sum is σ = 81972. Its totient is φ = 80512.

The previous prime is 81239. The next prime is 81281. The reversal of 81241 is 14218.

It is a happy number.

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: 14218 = 2 ⋅7109.

It can be written as a sum of positive squares in 2 ways, for example, as 48841 + 32400 = 221^2 + 180^2 .

It is a cyclic number.

It is not a de Polignac number, because 81241 - 2¹ = 81239 is a prime.

It is a Duffinian number.

81241 is a lucky number.

It is a plaindrome in base 7.

It is not an unprimeable number, because it can be changed into a prime (81281) 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, 160 + ... + 433.

It is an arithmetic number, because the mean of its divisors is an integer number (20493).

2⁸¹²⁴¹ is an apocalyptic number.

It is an amenable number.

81241 is a deficient number, since it is larger than the sum of its proper divisors (731).

81241 is a wasteful number, since it uses less digits than its factorization.

81241 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 730.

The product of its digits is 64, while the sum is 16.

The square root of 81241 is about 285.0280687932. The cubic root of 81241 is about 43.3103559973.

Subtracting from 81241 its sum of digits (16), we obtain a square (81225 = 285²).

Adding to 81241 its reverse (14218), we get a palindrome (95459).

The spelling of 81241 in words is "eighty-one thousand, two hundred forty-one".