12156147217 has 2 divisors, whose sum is σ = 12156147218. Its totient is φ = 12156147216.

The previous prime is 12156147209. The next prime is 12156147247. The reversal of 12156147217 is 71274165121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11450926081 + 705221136 = 107009^2 + 26556^2 .

It is a cyclic number.

It is not a de Polignac number, because 12156147217 - 2³ = 12156147209 is a prime.

It is a super-2 number, since 2×12156147217² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (12156147247) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6078073608 + 6078073609.

It is an arithmetic number, because the mean of its divisors is an integer number (6078073609).

Almost surely, 2^12156147217 is an apocalyptic number.

It is an amenable number.

12156147217 is a deficient number, since it is larger than the sum of its proper divisors (1).

12156147217 is an equidigital number, since it uses as much as digits as its factorization.

12156147217 is an evil number, because the sum of its binary digits is even.

The product of its digits is 23520, while the sum is 37.

The spelling of 12156147217 in words is "twelve billion, one hundred fifty-six million, one hundred forty-seven thousand, two hundred seventeen".