13991656 has 32 divisors (see below), whose sum is σ = 30600000. Its totient is φ = 5995248.

The previous prime is 13991651. The next prime is 13991687. The reversal of 13991656 is 65619931.

It is a zygodrome in base 7.

It is not an unprimeable number, because it can be changed into a prime (13991651) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 195 + ... + 5293.

It is an arithmetic number, because the mean of its divisors is an integer number (956250).

Almost surely, 2^13991656 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 13991656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15300000).

13991656 is an abundant number, since it is smaller than the sum of its proper divisors (16608344).

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

13991656 is an equidigital number, since it uses as much as digits as its factorization.

13991656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5126 (or 5108 counting only the distinct ones).

The product of its digits is 43740, while the sum is 40.

The square root of 13991656 is about 3740.5422066861. The cubic root of 13991656 is about 240.9663354089.

The spelling of 13991656 in words is "thirteen million, nine hundred ninety-one thousand, six hundred fifty-six".