1306263512681 has 2 divisors, whose sum is σ = 1306263512682. Its totient is φ = 1306263512680.

The previous prime is 1306263512639. The next prime is 1306263512699. The reversal of 1306263512681 is 1862153626031.

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., 1230757266025 + 75506246656 = 1109395^2 + 274784^2 .

It is an emirp because it is prime and its reverse (1862153626031) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1306263512681 is a prime.

It is a super-2 number, since 2×1306263512681² (a number of 25 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (1306263512621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 653131756340 + 653131756341.

It is an arithmetic number, because the mean of its divisors is an integer number (653131756341).

Almost surely, 2^{1306263512681} is an apocalyptic number.

It is an amenable number.

1306263512681 is a deficient number, since it is larger than the sum of its proper divisors (1).

1306263512681 is an equidigital number, since it uses as much as digits as its factorization.

1306263512681 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 311040, while the sum is 44.

The spelling of 1306263512681 in words is "one trillion, three hundred six billion, two hundred sixty-three million, five hundred twelve thousand, six hundred eighty-one".