205501 has 4 divisors (see below), whose sum is σ = 207900. Its totient is φ = 203104.

The previous prime is 205493. The next prime is 205507. The reversal of 205501 is 105502.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 106276 + 99225 = 326^2 + 315^2 .

It is a cyclic number.

It is not a de Polignac number, because 205501 - 2³ = 205493 is a prime.

It is a super-2 number, since 2×205501² = 84461322002, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205507) 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, 1066 + ... + 1243.

It is an arithmetic number, because the mean of its divisors is an integer number (51975).

2²⁰⁵⁵⁰¹ is an apocalyptic number.

It is an amenable number.

205501 is a deficient number, since it is larger than the sum of its proper divisors (2399).

205501 is an equidigital number, since it uses as much as digits as its factorization.

205501 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2398.

The product of its (nonzero) digits is 50, while the sum is 13.

The square root of 205501 is about 453.3221812354. The cubic root of 205501 is about 59.0116801543.

Subtracting from 205501 its reverse (105502), we obtain a palindrome (99999).

The spelling of 205501 in words is "two hundred five thousand, five hundred one".