12641813857 has 4 divisors (see below), whose sum is σ = 13049614336. Its totient is φ = 12234013380.

The previous prime is 12641813827. The next prime is 12641813869. The reversal of 12641813857 is 75831814621.

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 12641813857 - 2²³ = 12633425249 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12641813827) 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, 203900193 + ... + 203900254.

It is an arithmetic number, because the mean of its divisors is an integer number (3262403584).

Almost surely, 2^12641813857 is an apocalyptic number.

It is an amenable number.

12641813857 is a deficient number, since it is larger than the sum of its proper divisors (407800479).

12641813857 is an equidigital number, since it uses as much as digits as its factorization.

12641813857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 407800478.

The product of its digits is 322560, while the sum is 46.

The spelling of 12641813857 in words is "twelve billion, six hundred forty-one million, eight hundred thirteen thousand, eight hundred fifty-seven".