1211202021137 has 2 divisors, whose sum is σ = 1211202021138. Its totient is φ = 1211202021136.

The previous prime is 1211202021103. The next prime is 1211202021209. The reversal of 1211202021137 is 7311202021121.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1208330776081 + 2871245056 = 1099241^2 + 53584^2 .

It is an emirp because it is prime and its reverse (7311202021121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1211202021137 - 2¹⁰ = 1211202020113 is a prime.

It is not a weakly prime, because it can be changed into another prime (1211202020137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 605601010568 + 605601010569.

It is an arithmetic number, because the mean of its divisors is an integer number (605601010569).

Almost surely, 2^{1211202021137} is an apocalyptic number.

It is an amenable number.

1211202021137 is a deficient number, since it is larger than the sum of its proper divisors (1).

1211202021137 is an equidigital number, since it uses as much as digits as its factorization.

1211202021137 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 336, while the sum is 23.

Adding to 1211202021137 its reverse (7311202021121), we get a palindrome (8522404042258).

The spelling of 1211202021137 in words is "one trillion, two hundred eleven billion, two hundred two million, twenty-one thousand, one hundred thirty-seven".