13812720217 has 2 divisors, whose sum is σ = 13812720218. Its totient is φ = 13812720216.

The previous prime is 13812720209. The next prime is 13812720221. The reversal of 13812720217 is 71202721831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10754519616 + 3058200601 = 103704^2 + 55301^2 .

It is a cyclic number.

It is not a de Polignac number, because 13812720217 - 2³ = 13812720209 is a prime.

It is not a weakly prime, because it can be changed into another prime (13812720247) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6906360108 + 6906360109.

It is an arithmetic number, because the mean of its divisors is an integer number (6906360109).

Almost surely, 2^13812720217 is an apocalyptic number.

It is an amenable number.

13812720217 is a deficient number, since it is larger than the sum of its proper divisors (1).

13812720217 is an equidigital number, since it uses as much as digits as its factorization.

13812720217 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9408, while the sum is 34.

The spelling of 13812720217 in words is "thirteen billion, eight hundred twelve million, seven hundred twenty thousand, two hundred seventeen".