1216 has 14 divisors (see below), whose sum is σ = 2540. Its totient is φ = 576.

The previous prime is 1213. The next prime is 1217. The reversal of 1216 is 6121.

Adding to 1216 its reverse (6121), we get a palindrome (7337).

It can be divided in two parts, 12 and 16, that added together give a triangular number (28 = T_{7}).

1216 is nontrivially palindromic in base 13.

It is an alternating number because its digits alternate between odd and even.

1216 is an undulating number in base 13.

It is a plaindrome in base 7.

It is a nialpdrome in base 12.

It is a zygodrome in base 7.

It is not an unprimeable number, because it can be changed into a prime (1213) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (3) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55 + ... + 73.

1216 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

1216 is the 19-th nonagonal number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1270).

1216 is an abundant number, since it is smaller than the sum of its proper divisors (1324).

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

1216 is an equidigital number, since it uses as much as digits as its factorization.

1216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31 (or 21 counting only the distinct ones).

The product of its digits is 12, while the sum is 10.

The square root of 1216 is about 34.8711915483. The cubic root of 1216 is about 10.6736065949.

The spelling of 1216 in words is "one thousand, two hundred sixteen".

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