13666656 has 48 divisors (see below), whose sum is σ = 37119600. Its totient is φ = 4397568.

The previous prime is 13666607. The next prime is 13666661. The reversal of 13666656 is 65666631.

It is a tau number, because it is divible by the number of its divisors (48).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 330 + ... + 5238.

It is an arithmetic number, because the mean of its divisors is an integer number (773325).

Almost surely, 2^13666656 is an apocalyptic number.

13666656 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 13666656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (18559800).

13666656 is an abundant number, since it is smaller than the sum of its proper divisors (23452944).

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

13666656 is a wasteful number, since it uses less digits than its factorization.

13666656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4951 (or 4943 counting only the distinct ones).

The product of its digits is 116640, while the sum is 39.

The square root of 13666656 is about 3696.8440594648. The cubic root of 13666656 is about 239.0859678017.

The spelling of 13666656 in words is "thirteen million, six hundred sixty-six thousand, six hundred fifty-six".