12644681 has 4 divisors (see below), whose sum is σ = 14451072. Its totient is φ = 10838292.

The previous prime is 12644669. The next prime is 12644701. The reversal of 12644681 is 18644621.

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-12644681 is a prime.

It is a super-2 number, since 2×12644681² = 319775915183522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12647681) 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, 903185 + ... + 903198.

It is an arithmetic number, because the mean of its divisors is an integer number (3612768).

Almost surely, 2^12644681 is an apocalyptic number.

It is an amenable number.

12644681 is a deficient number, since it is larger than the sum of its proper divisors (1806391).

12644681 is an equidigital number, since it uses as much as digits as its factorization.

12644681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1806390.

The product of its digits is 9216, while the sum is 32.

The square root of 12644681 is about 3555.9360230465. The cubic root of 12644681 is about 232.9714087484.

The spelling of 12644681 in words is "twelve million, six hundred forty-four thousand, six hundred eighty-one".