1315121363561 has 2 divisors, whose sum is σ = 1315121363562. Its totient is φ = 1315121363560.

The previous prime is 1315121363531. The next prime is 1315121363617. The reversal of 1315121363561 is 1653631215131.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1213564421161 + 101556942400 = 1101619^2 + 318680^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1315121363561 is a prime.

It is not a weakly prime, because it can be changed into another prime (1315121363531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 657560681780 + 657560681781.

It is an arithmetic number, because the mean of its divisors is an integer number (657560681781).

Almost surely, 2^{1315121363561} is an apocalyptic number.

It is an amenable number.

1315121363561 is a deficient number, since it is larger than the sum of its proper divisors (1).

1315121363561 is an equidigital number, since it uses as much as digits as its factorization.

1315121363561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 48600, while the sum is 38.

Adding to 1315121363561 its reverse (1653631215131), we get a palindrome (2968752578692).

The spelling of 1315121363561 in words is "one trillion, three hundred fifteen billion, one hundred twenty-one million, three hundred sixty-three thousand, five hundred sixty-one".