1211210011997 has 2 divisors, whose sum is σ = 1211210011998. Its totient is φ = 1211210011996.

The previous prime is 1211210011993. The next prime is 1211210012027. The reversal of 1211210011997 is 7991100121121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 919362639556 + 291847372441 = 958834^2 + 540229^2 .

It is a cyclic number.

It is not a de Polignac number, because 1211210011997 - 2² = 1211210011993 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1211210011993) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 605605005998 + 605605005999.

It is an arithmetic number, because the mean of its divisors is an integer number (605605005999).

Almost surely, 2^{1211210011997} is an apocalyptic number.

It is an amenable number.

1211210011997 is a deficient number, since it is larger than the sum of its proper divisors (1).

1211210011997 is an equidigital number, since it uses as much as digits as its factorization.

1211210011997 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2268, while the sum is 35.

The spelling of 1211210011997 in words is "one trillion, two hundred eleven billion, two hundred ten million, eleven thousand, nine hundred ninety-seven".