1361331535261 has 2 divisors, whose sum is σ = 1361331535262. Its totient is φ = 1361331535260.

The previous prime is 1361331535253. The next prime is 1361331535321. The reversal of 1361331535261 is 1625351331631.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1307649425625 + 53682109636 = 1143525^2 + 231694^2 .

It is a cyclic number.

It is not a de Polignac number, because 1361331535261 - 2³ = 1361331535253 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1361331535561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 680665767630 + 680665767631.

It is an arithmetic number, because the mean of its divisors is an integer number (680665767631).

Almost surely, 2^{1361331535261} is an apocalyptic number.

It is an amenable number.

1361331535261 is a deficient number, since it is larger than the sum of its proper divisors (1).

1361331535261 is an equidigital number, since it uses as much as digits as its factorization.

1361331535261 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 145800, while the sum is 40.

Adding to 1361331535261 its reverse (1625351331631), we get a palindrome (2986682866892).

The spelling of 1361331535261 in words is "one trillion, three hundred sixty-one billion, three hundred thirty-one million, five hundred thirty-five thousand, two hundred sixty-one".