2101205 has 4 divisors (see below), whose sum is σ = 2521452. Its totient is φ = 1680960.

The previous prime is 2101199. The next prime is 2101207. The reversal of 2101205 is 5021012.

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 877969 + 1223236 = 937^2 + 1106^2 .

It is not a de Polignac number, because 2101205 - 2⁴ = 2101189 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 (2101207) 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, 210116 + ... + 210125.

It is an arithmetic number, because the mean of its divisors is an integer number (630363).

2^2101205 is an apocalyptic number.

It is an amenable number.

2101205 is a deficient number, since it is larger than the sum of its proper divisors (420247).

2101205 is an equidigital number, since it uses as much as digits as its factorization.

2101205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 420246.

The product of its (nonzero) digits is 20, while the sum is 11.

The square root of 2101205 is about 1449.5533794931. The cubic root of 2101205 is about 128.0824054327.

Adding to 2101205 its reverse (5021012), we get a palindrome (7122217).

The spelling of 2101205 in words is "two million, one hundred one thousand, two hundred five".