213111321209 has 2 divisors, whose sum is σ = 213111321210. Its totient is φ = 213111321208.

The previous prime is 213111321197. The next prime is 213111321217. The reversal of 213111321209 is 902123111312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 166420754809 + 46690566400 = 407947^2 + 216080^2 .

It is a cyclic number.

It is not a de Polignac number, because 213111321209 - 2²⁰ = 213110272633 is a prime.

It is not a weakly prime, because it can be changed into another prime (213111321109) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106555660604 + 106555660605.

It is an arithmetic number, because the mean of its divisors is an integer number (106555660605).

Almost surely, 2^213111321209 is an apocalyptic number.

It is an amenable number.

213111321209 is a deficient number, since it is larger than the sum of its proper divisors (1).

213111321209 is an equidigital number, since it uses as much as digits as its factorization.

213111321209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 648, while the sum is 26.

The spelling of 213111321209 in words is "two hundred thirteen billion, one hundred eleven million, three hundred twenty-one thousand, two hundred nine".