13561216 has 32 divisors (see below), whose sum is σ = 27540000. Its totient is φ = 6649344.

The previous prime is 13561199. The next prime is 13561259. The reversal of 13561216 is 61216531.

13561216 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5785 + ... + 7783.

It is an arithmetic number, because the mean of its divisors is an integer number (860625).

Almost surely, 2^13561216 is an apocalyptic number.

13561216 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 13561216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13770000).

13561216 is an abundant number, since it is smaller than the sum of its proper divisors (13978784).

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

13561216 is an equidigital number, since it uses as much as digits as its factorization.

13561216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2066 (or 2054 counting only the distinct ones).

The product of its digits is 1080, while the sum is 25.

The square root of 13561216 is about 3682.5556343387. Note that the first 3 decimals coincide. The cubic root of 13561216 is about 238.4695201363.

Adding to 13561216 its reverse (61216531), we get a palindrome (74777747).

The spelling of 13561216 in words is "thirteen million, five hundred sixty-one thousand, two hundred sixteen".