12545665261 has 4 divisors (see below), whose sum is σ = 13091128992. Its totient is φ = 12000201532.

The previous prime is 12545665241. The next prime is 12545665283. The reversal of 12545665261 is 16256654521.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 12545665261 - 2⁵ = 12545665229 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 (12545665241) 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, 272731831 + ... + 272731876.

It is an arithmetic number, because the mean of its divisors is an integer number (3272782248).

Almost surely, 2^12545665261 is an apocalyptic number.

It is an amenable number.

12545665261 is a deficient number, since it is larger than the sum of its proper divisors (545463731).

12545665261 is an equidigital number, since it uses as much as digits as its factorization.

12545665261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 545463730.

The product of its digits is 432000, while the sum is 43.

The spelling of 12545665261 in words is "twelve billion, five hundred forty-five million, six hundred sixty-five thousand, two hundred sixty-one".