13216721297 has 8 divisors (see below), whose sum is σ = 14246975400. Its totient is φ = 12188407680.

The previous prime is 13216721291. The next prime is 13216721369. The reversal of 13216721297 is 79212761231.

It is a happy number.

It is a Cunningham number, because it is equal to 114964²+1.

It can be written as a sum of positive squares in 4 ways, for example, as 94789696 + 13121931601 = 9736^2 + 114551^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 13216721297 - 2¹⁴ = 13216704913 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13216721291) 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, 470954 + ... + 498227.

It is an arithmetic number, because the mean of its divisors is an integer number (1780871925).

Almost surely, 2^13216721297 is an apocalyptic number.

It is an amenable number.

13216721297 is a deficient number, since it is larger than the sum of its proper divisors (1030254103).

13216721297 is a wasteful number, since it uses less digits than its factorization.

13216721297 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 970243.

The product of its digits is 63504, while the sum is 41.

The spelling of 13216721297 in words is "thirteen billion, two hundred sixteen million, seven hundred twenty-one thousand, two hundred ninety-seven".