1212842209 has 2 divisors, whose sum is σ = 1212842210. Its totient is φ = 1212842208.

The previous prime is 1212842161. The next prime is 1212842227. The reversal of 1212842209 is 9022482121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 657768609 + 555073600 = 25647^2 + 23560^2 .

It is an emirp because it is prime and its reverse (9022482121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1212842209 - 2¹³ = 1212834017 is a prime.

It is not a weakly prime, because it can be changed into another prime (1212843209) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 606421104 + 606421105.

It is an arithmetic number, because the mean of its divisors is an integer number (606421105).

Almost surely, 2^1212842209 is an apocalyptic number.

It is an amenable number.

1212842209 is a deficient number, since it is larger than the sum of its proper divisors (1).

1212842209 is an equidigital number, since it uses as much as digits as its factorization.

1212842209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4608, while the sum is 31.

The square root of 1212842209 is about 34825.8841811662. The cubic root of 1212842209 is about 1066.4359271195.

The spelling of 1212842209 in words is "one billion, two hundred twelve million, eight hundred forty-two thousand, two hundred nine".