1265816738317 has 2 divisors, whose sum is σ = 1265816738318. Its totient is φ = 1265816738316.

The previous prime is 1265816738311. The next prime is 1265816738321. The reversal of 1265816738317 is 7138376185621.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 741081661321 + 524735076996 = 860861^2 + 724386^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1265816738317 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1265816738311) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 632908369158 + 632908369159.

It is an arithmetic number, because the mean of its divisors is an integer number (632908369159).

Almost surely, 2^{1265816738317} is an apocalyptic number.

It is an amenable number.

1265816738317 is a deficient number, since it is larger than the sum of its proper divisors (1).

1265816738317 is an equidigital number, since it uses as much as digits as its factorization.

1265816738317 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10160640, while the sum is 58.

The spelling of 1265816738317 in words is "one trillion, two hundred sixty-five billion, eight hundred sixteen million, seven hundred thirty-eight thousand, three hundred seventeen".