11561166123563 has 12 divisors (see below), whose sum is σ = 13498698645360. Its totient is φ = 9872732398032.

The previous prime is 11561166123523. The next prime is 11561166123613. The reversal of 11561166123563 is 36532166116511.

It is not a de Polignac number, because 11561166123563 - 2¹⁸ = 11561165861419 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11561166123503) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 438541031 + ... + 438567392.

It is an arithmetic number, because the mean of its divisors is an integer number (1124891553780).

Almost surely, 2^{11561166123563} is an apocalyptic number.

11561166123563 is a deficient number, since it is larger than the sum of its proper divisors (1937532521797).

11561166123563 is an equidigital number, since it uses as much as digits as its factorization.

11561166123563 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 877108706 (or 877108699 counting only the distinct ones).

The product of its digits is 583200, while the sum is 47.

The spelling of 11561166123563 in words is "eleven trillion, five hundred sixty-one billion, one hundred sixty-six million, one hundred twenty-three thousand, five hundred sixty-three".