13216491369 has 9 divisors (see below), whose sum is σ = 19090985719. Its totient is φ = 8810764320.

The previous prime is 13216491317. The next prime is 13216491391. The reversal of 13216491369 is 96319461231.

The square root of 13216491369 is 114963.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 8169809769 + 5046681600 = 90387^2 + 71040^2 .

It is a tau number, because it is divible by the number of its divisors (9).

It is not a de Polignac number, because 13216491369 - 2¹⁵ = 13216458601 is a prime.

It is a super-2 number, since 2×13216491369² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (13216491569) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 325729 + ... + 364049.

Almost surely, 2^13216491369 is an apocalyptic number.

13216491369 is the 114963-rd square number.

13216491369 is the 57482-nd centered octagonal number.

It is an amenable number.

13216491369 is a deficient number, since it is larger than the sum of its proper divisors (5874494350).

13216491369 is an frugal number, since it uses more digits than its factorization.

13216491369 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76648 (or 38324 counting only the distinct ones).

The product of its digits is 209952, while the sum is 45.

The spelling of 13216491369 in words is "thirteen billion, two hundred sixteen million, four hundred ninety-one thousand, three hundred sixty-nine".