1311643046261 has 2 divisors, whose sum is σ = 1311643046262. Its totient is φ = 1311643046260.

The previous prime is 1311643046243. The next prime is 1311643046267. The reversal of 1311643046261 is 1626403461131.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1287464662225 + 24178384036 = 1134665^2 + 155494^2 .

It is a cyclic number.

It is not a de Polignac number, because 1311643046261 - 2³⁰ = 1310569304437 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1311643046267) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 655821523130 + 655821523131.

It is an arithmetic number, because the mean of its divisors is an integer number (655821523131).

Almost surely, 2^{1311643046261} is an apocalyptic number.

It is an amenable number.

1311643046261 is a deficient number, since it is larger than the sum of its proper divisors (1).

1311643046261 is an equidigital number, since it uses as much as digits as its factorization.

1311643046261 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 62208, while the sum is 38.

The spelling of 1311643046261 in words is "one trillion, three hundred eleven billion, six hundred forty-three million, forty-six thousand, two hundred sixty-one".