81461 has 6 divisors (see below), whose sum is σ = 85890. Its totient is φ = 77168.

The previous prime is 81457. The next prime is 81463. The reversal of 81461 is 16418.

It can be written as a sum of positive squares in 3 ways, for example, as 28561 + 52900 = 169^2 + 230^2 .

It is not a de Polignac number, because 81461 - 2² = 81457 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 (81463) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1511 + ... + 1563.

It is an arithmetic number, because the mean of its divisors is an integer number (14315).

2⁸¹⁴⁶¹ is an apocalyptic number.

It is an amenable number.

81461 is a deficient number, since it is larger than the sum of its proper divisors (4429).

81461 is an equidigital number, since it uses as much as digits as its factorization.

81461 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 135 (or 82 counting only the distinct ones).

The product of its digits is 192, while the sum is 20.

The square root of 81461 is about 285.4137347781. The cubic root of 81461 is about 43.3494154640.

Adding to 81461 its reverse (16418), we get a palindrome (97879).

The spelling of 81461 in words is "eighty-one thousand, four hundred sixty-one".