1211031212081 has 2 divisors, whose sum is σ = 1211031212082. Its totient is φ = 1211031212080.

The previous prime is 1211031212059. The next prime is 1211031212087. The reversal of 1211031212081 is 1802121301121.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1186010299681 + 25020912400 = 1089041^2 + 158180^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1211031212081 is a prime.

It is a super-2 number, since 2×1211031212081² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1211031212087) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 605515606040 + 605515606041.

It is an arithmetic number, because the mean of its divisors is an integer number (605515606041).

Almost surely, 2^{1211031212081} is an apocalyptic number.

It is an amenable number.

1211031212081 is a deficient number, since it is larger than the sum of its proper divisors (1).

1211031212081 is an equidigital number, since it uses as much as digits as its factorization.

1211031212081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 192, while the sum is 23.

The spelling of 1211031212081 in words is "one trillion, two hundred eleven billion, thirty-one million, two hundred twelve thousand, eighty-one".