13665664 has 32 divisors (see below), whose sum is σ = 27399240. Its totient is φ = 6789120.

The previous prime is 13665661. The next prime is 13665667. The reversal of 13665664 is 46656631.

It is an interprime number because it is at equal distance from previous prime (13665661) and next prime (13665667).

It is a tau number, because it is divible by the number of its divisors (32).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13665661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 30627 + ... + 31069.

Almost surely, 2^13665664 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 13665664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13699620).

13665664 is an abundant number, since it is smaller than the sum of its proper divisors (13733576).

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

13665664 is an equidigital number, since it uses as much as digits as its factorization.

13665664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 698 (or 686 counting only the distinct ones).

The product of its digits is 77760, while the sum is 37.

The square root of 13665664 is about 3696.7098885360. The cubic root of 13665664 is about 239.0801829431.

The spelling of 13665664 in words is "thirteen million, six hundred sixty-five thousand, six hundred sixty-four".