12805864569 has 27 divisors (see below), whose sum is σ = 18810972453. Its totient is φ = 8394883992.

The previous prime is 12805864559. The next prime is 12805864571. The reversal of 12805864569 is 96546850821.

The square root of 12805864569 is 113163.

It is a perfect power (a square), and thus also a powerful number.

12805864569 is a `hidden beast` number, since 1 + 2 + 8 + 0 + 586 + 4 + 56 + 9 = 666.

It is not a de Polignac number, because 12805864569 - 2²³ = 12797475961 is a prime.

It is a super-2 number, since 2×12805864569² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (12805864559) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 22745482 + ... + 22746044.

Almost surely, 2^12805864569 is an apocalyptic number.

12805864569 is the 113163-rd square number.

12805864569 is the 56582-nd centered octagonal number.

It is an amenable number.

12805864569 is a deficient number, since it is larger than the sum of its proper divisors (6005107884).

12805864569 is an frugal number, since it uses more digits than its factorization.

12805864569 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1266 (or 633 counting only the distinct ones).

The product of its (nonzero) digits is 4147200, while the sum is 54.

The spelling of 12805864569 in words is "twelve billion, eight hundred five million, eight hundred sixty-four thousand, five hundred sixty-nine".