11661216 has 144 divisors (see below), whose sum is σ = 37116576. Its totient is φ = 3193344.

The previous prime is 11661197. The next prime is 11661229. The reversal of 11661216 is 61216611.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 174015 + ... + 174081.

It is an arithmetic number, because the mean of its divisors is an integer number (257754).

Almost surely, 2^11661216 is an apocalyptic number.

11661216 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 11661216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (18558288).

11661216 is an abundant number, since it is smaller than the sum of its proper divisors (25455360).

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

11661216 is a wasteful number, since it uses less digits than its factorization.

11661216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 131 (or 116 counting only the distinct ones).

The product of its digits is 432, while the sum is 24.

The square root of 11661216 is about 3414.8522662042. The cubic root of 11661216 is about 226.7677442315.

Adding to 11661216 its reverse (61216611), we get a palindrome (72877827).

The spelling of 11661216 in words is "eleven million, six hundred sixty-one thousand, two hundred sixteen".