13155126305561 has 2 divisors, whose sum is σ = 13155126305562. Its totient is φ = 13155126305560.

The previous prime is 13155126305521. The next prime is 13155126305617. The reversal of 13155126305561 is 16550362155131.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11218353083161 + 1936773222400 = 3349381^2 + 1391680^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13155126305561 is a prime.

It is not a weakly prime, because it can be changed into another prime (13155126305521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6577563152780 + 6577563152781.

It is an arithmetic number, because the mean of its divisors is an integer number (6577563152781).

Almost surely, 2^{13155126305561} is an apocalyptic number.

It is an amenable number.

13155126305561 is a deficient number, since it is larger than the sum of its proper divisors (1).

13155126305561 is an equidigital number, since it uses as much as digits as its factorization.

13155126305561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 405000, while the sum is 44.

The spelling of 13155126305561 in words is "thirteen trillion, one hundred fifty-five billion, one hundred twenty-six million, three hundred five thousand, five hundred sixty-one".