12689664 has 144 divisors (see below), whose sum is σ = 38459904. Its totient is φ = 3686400.

The previous prime is 12689657. The next prime is 12689669. The reversal of 12689664 is 46698621.

It is a super-2 number, since 2×12689664² = 322055144865792, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12689669) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 309484 + ... + 309524.

Almost surely, 2^12689664 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 12689664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (19229952).

12689664 is an abundant number, since it is smaller than the sum of its proper divisors (25770240).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

12689664 is a wasteful number, since it uses less digits than its factorization.

12689664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 104 (or 90 counting only the distinct ones).

The product of its digits is 124416, while the sum is 42.

The square root of 12689664 is about 3562.2554652916. The cubic root of 12689664 is about 233.2473442785.

The spelling of 12689664 in words is "twelve million, six hundred eighty-nine thousand, six hundred sixty-four".