1211211202009 has 2 divisors, whose sum is σ = 1211211202010. Its totient is φ = 1211211202008.

The previous prime is 1211211201973. The next prime is 1211211202027. The reversal of 1211211202009 is 9002021121121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 701205264400 + 510005937609 = 837380^2 + 714147^2 .

It is a cyclic number.

It is not a de Polignac number, because 1211211202009 - 2²⁷ = 1211076984281 is a prime.

It is not a weakly prime, because it can be changed into another prime (1211211202049) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 605605601004 + 605605601005.

It is an arithmetic number, because the mean of its divisors is an integer number (605605601005).

Almost surely, 2^{1211211202009} is an apocalyptic number.

It is an amenable number.

1211211202009 is a deficient number, since it is larger than the sum of its proper divisors (1).

1211211202009 is an equidigital number, since it uses as much as digits as its factorization.

1211211202009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 144, while the sum is 22.

The spelling of 1211211202009 in words is "one trillion, two hundred eleven billion, two hundred eleven million, two hundred two thousand, nine".