11721112216 has 72 divisors (see below), whose sum is σ = 24418728180. Its totient is φ = 5270584000.

The previous prime is 11721112199. The next prime is 11721112231. The reversal of 11721112216 is 61221112711.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 9873975 + ... + 9875161.

Almost surely, 2^11721112216 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 11721112216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (12209364090).

11721112216 is an abundant number, since it is smaller than the sum of its proper divisors (12697615964).

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

11721112216 is a wasteful number, since it uses less digits than its factorization.

11721112216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1417 (or 1301 counting only the distinct ones).

The product of its digits is 336, while the sum is 25.

Adding to 11721112216 its reverse (61221112711), we get a palindrome (72942224927).

The spelling of 11721112216 in words is "eleven billion, seven hundred twenty-one million, one hundred twelve thousand, two hundred sixteen".