13021216 has 48 divisors (see below), whose sum is σ = 27952344. Its totient is φ = 5935104.

The previous prime is 13021207. The next prime is 13021219. The reversal of 13021216 is 61212031.

It can be written as a sum of positive squares in 4 ways, for example, as 2755600 + 10265616 = 1660^2 + 3204^2 .

It is a super-2 number, since 2×13021216² = 339104132237312, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (16).

It is a self number, because there is not a number n which added to its sum of digits gives 13021216.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13021219) 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, 46870 + ... + 47146.

Almost surely, 2^13021216 is an apocalyptic number.

13021216 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 13021216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13976172).

13021216 is an abundant number, since it is smaller than the sum of its proper divisors (14931128).

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

13021216 is a wasteful number, since it uses less digits than its factorization.

13021216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 413 (or 405 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 16.

The square root of 13021216 is about 3608.4922058943. The cubic root of 13021216 is about 235.2613118577.

Adding to 13021216 its reverse (61212031), we get a palindrome (74233247).

The spelling of 13021216 in words is "thirteen million, twenty-one thousand, two hundred sixteen".