12643609971 has 24 divisors (see below), whose sum is σ = 18292602384. Its totient is φ = 7736604160.

The previous prime is 12643609939. The next prime is 12643609973. The reversal of 12643609971 is 17990634621.

It is not a de Polignac number, because 12643609971 - 2⁵ = 12643609939 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 12643609971.

It is not an unprimeable number, because it can be changed into a prime (12643609973) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5140540 + ... + 5142998.

It is an arithmetic number, because the mean of its divisors is an integer number (762191766).

Almost surely, 2^12643609971 is an apocalyptic number.

12643609971 is a deficient number, since it is larger than the sum of its proper divisors (5648992413).

12643609971 is an frugal number, since it uses more digits than its factorization.

12643609971 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4979 (or 2520 counting only the distinct ones).

The product of its (nonzero) digits is 489888, while the sum is 48.

The spelling of 12643609971 in words is "twelve billion, six hundred forty-three million, six hundred nine thousand, nine hundred seventy-one".