12565043461 has 4 divisors (see below), whose sum is σ = 12565361452. Its totient is φ = 12564725472.

The previous prime is 12565043431. The next prime is 12565043479. The reversal of 12565043461 is 16434056521.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 16434056521 = 8179 ⋅2009299.

It can be written as a sum of positive squares in 2 ways, for example, as 11290125025 + 1274918436 = 106255^2 + 35706^2 .

It is a cyclic number.

It is not a de Polignac number, because 12565043461 - 2²⁷ = 12430825733 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 12565043461.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12565043401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 89640 + ... + 182113.

It is an arithmetic number, because the mean of its divisors is an integer number (3141340363).

Almost surely, 2^12565043461 is an apocalyptic number.

It is an amenable number.

12565043461 is a deficient number, since it is larger than the sum of its proper divisors (317991).

12565043461 is an equidigital number, since it uses as much as digits as its factorization.

12565043461 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 317990.

The product of its (nonzero) digits is 86400, while the sum is 37.

Adding to 12565043461 its reverse (16434056521), we get a palindrome (28999099982).

The spelling of 12565043461 in words is "twelve billion, five hundred sixty-five million, forty-three thousand, four hundred sixty-one".