1211053965181 has 2 divisors, whose sum is σ = 1211053965182. Its totient is φ = 1211053965180.

The previous prime is 1211053965179. The next prime is 1211053965241. The reversal of 1211053965181 is 1815693501121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1067192302500 + 143861662681 = 1033050^2 + 379291^2 .

It is an emirp because it is prime and its reverse (1815693501121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1211053965181 - 2¹ = 1211053965179 is a prime.

It is a super-2 number, since 2×1211053965181² (a number of 25 digits) contains 22 as substring.

Together with 1211053965179, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1211053968181) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 605526982590 + 605526982591.

It is an arithmetic number, because the mean of its divisors is an integer number (605526982591).

Almost surely, 2^{1211053965181} is an apocalyptic number.

It is an amenable number.

1211053965181 is a deficient number, since it is larger than the sum of its proper divisors (1).

1211053965181 is an equidigital number, since it uses as much as digits as its factorization.

1211053965181 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 64800, while the sum is 43.

The spelling of 1211053965181 in words is "one trillion, two hundred eleven billion, fifty-three million, nine hundred sixty-five thousand, one hundred eighty-one".