205101 has 12 divisors (see below), whose sum is σ = 319228. Its totient is φ = 126144.

The previous prime is 205097. The next prime is 205103. The reversal of 205101 is 101502.

205101 = 76² + 77² + ... + 101².

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 15876 + 189225 = 126^2 + 435^2 .

It is not a de Polignac number, because 205101 - 2² = 205097 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is an Ulam number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205103) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 760 + ... + 993.

2²⁰⁵¹⁰¹ is an apocalyptic number.

It is an amenable number.

205101 is a deficient number, since it is larger than the sum of its proper divisors (114127).

205101 is a wasteful number, since it uses less digits than its factorization.

205101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1772 (or 1769 counting only the distinct ones).

The product of its (nonzero) digits is 10, while the sum is 9.

The square root of 205101 is about 452.8807790136. The cubic root of 205101 is about 58.9733672769.

Adding to 205101 its reverse (101502), we get a palindrome (306603).

The spelling of 205101 in words is "two hundred five thousand, one hundred one".