12817622861 has 4 divisors (see below), whose sum is σ = 12835254432. Its totient is φ = 12799991292.

The previous prime is 12817622833. The next prime is 12817622887. The reversal of 12817622861 is 16822671821.

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 a de Polignac number, because none of the positive numbers 2^k-12817622861 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 (12817622161) 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, 8814695 + ... + 8816148.

It is an arithmetic number, because the mean of its divisors is an integer number (3208813608).

Almost surely, 2^12817622861 is an apocalyptic number.

It is an amenable number.

12817622861 is a deficient number, since it is larger than the sum of its proper divisors (17631571).

12817622861 is an equidigital number, since it uses as much as digits as its factorization.

12817622861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17631570.

The product of its digits is 129024, while the sum is 44.

The spelling of 12817622861 in words is "twelve billion, eight hundred seventeen million, six hundred twenty-two thousand, eight hundred sixty-one".