1316261535661 has 2 divisors, whose sum is σ = 1316261535662. Its totient is φ = 1316261535660.

The previous prime is 1316261535629. The next prime is 1316261535679. The reversal of 1316261535661 is 1665351626131.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1092348974025 + 223912561636 = 1045155^2 + 473194^2 .

It is a cyclic number.

It is not a de Polignac number, because 1316261535661 - 2⁵ = 1316261535629 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1316261535691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 658130767830 + 658130767831.

It is an arithmetic number, because the mean of its divisors is an integer number (658130767831).

Almost surely, 2^{1316261535661} is an apocalyptic number.

It is an amenable number.

1316261535661 is a deficient number, since it is larger than the sum of its proper divisors (1).

1316261535661 is an equidigital number, since it uses as much as digits as its factorization.

1316261535661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 583200, while the sum is 46.

The spelling of 1316261535661 in words is "one trillion, three hundred sixteen billion, two hundred sixty-one million, five hundred thirty-five thousand, six hundred sixty-one".