205481 has 4 divisors (see below), whose sum is σ = 209412. Its totient is φ = 201552.

The previous prime is 205477. The next prime is 205483. The reversal of 205481 is 184502.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 184502 = 2 ⋅92251.

It can be written as a sum of positive squares in 2 ways, for example, as 99856 + 105625 = 316^2 + 325^2 .

It is a cyclic number.

It is not a de Polignac number, because 205481 - 2² = 205477 is a prime.

It is a super-2 number, since 2×205481² = 84444882722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (205483) 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, 1886 + ... + 1991.

It is an arithmetic number, because the mean of its divisors is an integer number (52353).

2²⁰⁵⁴⁸¹ is an apocalyptic number.

It is an amenable number.

205481 is a deficient number, since it is larger than the sum of its proper divisors (3931).

205481 is an equidigital number, since it uses as much as digits as its factorization.

205481 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3930.

The product of its (nonzero) digits is 320, while the sum is 20.

The square root of 205481 is about 453.3001213324. The cubic root of 205481 is about 59.0097656917.

Adding to 205481 its reverse (184502), we get a palindrome (389983).

It can be divided in two parts, 205 and 481, that added together give a palindrome (686).

The spelling of 205481 in words is "two hundred five thousand, four hundred eighty-one".