12540205 has 4 divisors (see below), whose sum is σ = 15048252. Its totient is φ = 10032160.

The previous prime is 12540181. The next prime is 12540217. The reversal of 12540205 is 50204521.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 50204521 = 43 ⋅1167547.

It can be written as a sum of positive squares in 2 ways, for example, as 8655364 + 3884841 = 2942^2 + 1971^2 .

It is not a de Polignac number, because 12540205 - 2⁵ = 12540173 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1254016 + ... + 1254025.

It is an arithmetic number, because the mean of its divisors is an integer number (3762063).

Almost surely, 2^12540205 is an apocalyptic number.

It is an amenable number.

12540205 is a deficient number, since it is larger than the sum of its proper divisors (2508047).

12540205 is an equidigital number, since it uses as much as digits as its factorization.

12540205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2508046.

The product of its (nonzero) digits is 400, while the sum is 19.

The square root of 12540205 is about 3541.2151869097. The cubic root of 12540205 is about 232.3279954934.

Adding to 12540205 its reverse (50204521), we get a palindrome (62744726).

The spelling of 12540205 in words is "twelve million, five hundred forty thousand, two hundred five".