13245116561 has 2 divisors, whose sum is σ = 13245116562. Its totient is φ = 13245116560.

The previous prime is 13245116557. The next prime is 13245116567. The reversal of 13245116561 is 16561154231.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8467680400 + 4777436161 = 92020^2 + 69119^2 .

It is a cyclic number.

It is not a de Polignac number, because 13245116561 - 2² = 13245116557 is a prime.

It is a super-2 number, since 2×13245116561² (a number of 21 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 (13245116567) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6622558280 + 6622558281.

It is an arithmetic number, because the mean of its divisors is an integer number (6622558281).

Almost surely, 2^13245116561 is an apocalyptic number.

It is an amenable number.

13245116561 is a deficient number, since it is larger than the sum of its proper divisors (1).

13245116561 is an equidigital number, since it uses as much as digits as its factorization.

13245116561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 21600, while the sum is 35.

The spelling of 13245116561 in words is "thirteen billion, two hundred forty-five million, one hundred sixteen thousand, five hundred sixty-one".