25662340205 has 4 divisors (see below), whose sum is σ = 30794808252. Its totient is φ = 20529872160.

The previous prime is 25662340159. The next prime is 25662340219. The reversal of 25662340205 is 50204326652.

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 7831011049 + 17831329156 = 88493^2 + 133534^2 .

It is not a de Polignac number, because 25662340205 - 2¹⁰ = 25662339181 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, 2566234016 + ... + 2566234025.

It is an arithmetic number, because the mean of its divisors is an integer number (7698702063).

Almost surely, 2^25662340205 is an apocalyptic number.

It is an amenable number.

25662340205 is a deficient number, since it is larger than the sum of its proper divisors (5132468047).

25662340205 is an equidigital number, since it uses as much as digits as its factorization.

25662340205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5132468046.

The product of its (nonzero) digits is 86400, while the sum is 35.

Adding to 25662340205 its reverse (50204326652), we get a palindrome (75866666857).

The spelling of 25662340205 in words is "twenty-five billion, six hundred sixty-two million, three hundred forty thousand, two hundred five".