1261681263331 has 2 divisors, whose sum is σ = 1261681263332. Its totient is φ = 1261681263330.

The previous prime is 1261681263313. The next prime is 1261681263341. The reversal of 1261681263331 is 1333621861621.

Together with previous prime (1261681263313) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1261681263331 - 2⁷ = 1261681263203 is a prime.

It is a super-2 number, since 2×1261681263331² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1261681263341) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 630840631665 + 630840631666.

It is an arithmetic number, because the mean of its divisors is an integer number (630840631666).

Almost surely, 2^{1261681263331} is an apocalyptic number.

1261681263331 is a deficient number, since it is larger than the sum of its proper divisors (1).

1261681263331 is an equidigital number, since it uses as much as digits as its factorization.

1261681263331 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 186624, while the sum is 43.

The spelling of 1261681263331 in words is "one trillion, two hundred sixty-one billion, six hundred eighty-one million, two hundred sixty-three thousand, three hundred thirty-one".